From 08b581228883f3b34734cb1b74657dbb8ea6d18f Mon Sep 17 00:00:00 2001
From: agnostic-apollo <agnosticapollo@gmail.com>
Date: Mon, 23 Aug 2021 08:22:14 +0500
Subject: [PATCH] Added!: Convert extra-keys to agnosticism

The termux `extra-keys` have been moved to `termux-shared` library so that they can be imported and used by other apps for their own needs as long as they comply with GPLv3 license.

Almost everything is customizable and has no dependency on termux specific logic. Check the javadocs of files of `com.termux.shared.terminal.io.extrakeys` package for more info, specially, `ExtraKeysView`, `ExtraKeysInfo`, `ExtraKeyButton`, `TerminalExtraKeys` and  `TermuxTerminalExtraKeys`.

Moreover, you can now long hold on `CTRL`, `ALT`, `SHIFT` and `FN` to lock those control keys. They will not be released when you press another key and will only be released by pressing the respective control key again.

Closes #2049, Closes #1861
---
 .../java/com/termux/app/TermuxActivity.java   |   2 +-
 .../properties/TermuxAppSharedProperties.java |  15 +-
 .../terminal/TermuxTerminalViewClient.java    |  16 +-
 .../terminal/io/TerminalToolbarViewPager.java |   6 +-
 .../terminal/io/TermuxTerminalExtraKeys.java  |  47 ++
 .../terminal/io/extrakeys/ExtraKeyButton.java |  92 ---
 .../terminal/io/extrakeys/ExtraKeysInfo.java  | 260 -------
 .../terminal/io/extrakeys/ExtraKeysView.java  | 401 -----------
 .../view_terminal_toolbar_extra_keys.xml      |   2 +-
 .../shared/terminal/io/TerminalExtraKeys.java |  77 +++
 .../terminal/io/extrakeys/ExtraKeyButton.java | 151 ++++
 .../io/extrakeys/ExtraKeysConstants.java      | 207 ++++++
 .../terminal/io/extrakeys/ExtraKeysInfo.java  | 211 ++++++
 .../terminal/io/extrakeys/ExtraKeysView.java  | 646 ++++++++++++++++++
 .../terminal/io/extrakeys/SpecialButton.java  |  52 ++
 .../io/extrakeys/SpecialButtonState.java      |  49 ++
 16 files changed, 1470 insertions(+), 764 deletions(-)
 create mode 100644 app/src/main/java/com/termux/app/terminal/io/TermuxTerminalExtraKeys.java
 delete mode 100644 app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeyButton.java
 delete mode 100644 app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeysInfo.java
 delete mode 100644 app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeysView.java
 create mode 100644 termux-shared/src/main/java/com/termux/shared/terminal/io/TerminalExtraKeys.java
 create mode 100644 termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeyButton.java
 create mode 100644 termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysConstants.java
 create mode 100644 termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysInfo.java
 create mode 100644 termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysView.java
 create mode 100644 termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/SpecialButton.java
 create mode 100644 termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/SpecialButtonState.java

diff --git a/app/src/main/java/com/termux/app/TermuxActivity.java b/app/src/main/java/com/termux/app/TermuxActivity.java
index 257ec38993..254b3bc50f 100644
--- a/app/src/main/java/com/termux/app/TermuxActivity.java
+++ b/app/src/main/java/com/termux/app/TermuxActivity.java
@@ -44,7 +44,7 @@
 import com.termux.app.terminal.io.TerminalToolbarViewPager;
 import com.termux.app.terminal.TermuxTerminalSessionClient;
 import com.termux.app.terminal.TermuxTerminalViewClient;
-import com.termux.app.terminal.io.extrakeys.ExtraKeysView;
+import com.termux.shared.terminal.io.extrakeys.ExtraKeysView;
 import com.termux.app.settings.properties.TermuxAppSharedProperties;
 import com.termux.shared.interact.TextInputDialogUtils;
 import com.termux.shared.logger.Logger;
diff --git a/app/src/main/java/com/termux/app/settings/properties/TermuxAppSharedProperties.java b/app/src/main/java/com/termux/app/settings/properties/TermuxAppSharedProperties.java
index 6c2e03713a..fabe683a3c 100644
--- a/app/src/main/java/com/termux/app/settings/properties/TermuxAppSharedProperties.java
+++ b/app/src/main/java/com/termux/app/settings/properties/TermuxAppSharedProperties.java
@@ -3,7 +3,9 @@
 import android.content.Context;
 
 import com.termux.app.terminal.io.KeyboardShortcut;
-import com.termux.app.terminal.io.extrakeys.ExtraKeysInfo;
+import com.termux.shared.terminal.io.extrakeys.ExtraKeysConstants;
+import com.termux.shared.terminal.io.extrakeys.ExtraKeysConstants.EXTRA_KEY_DISPLAY_MAPS;
+import com.termux.shared.terminal.io.extrakeys.ExtraKeysInfo;
 import com.termux.shared.logger.Logger;
 import com.termux.shared.settings.properties.TermuxPropertyConstants;
 import com.termux.shared.settings.properties.TermuxSharedProperties;
@@ -50,13 +52,20 @@ private void setExtraKeys() {
             // {@link #getExtraKeysStyleInternalPropertyValueFromValue(String)}
             String extrakeys = (String) getInternalPropertyValue(TermuxPropertyConstants.KEY_EXTRA_KEYS, true);
             String extraKeysStyle = (String) getInternalPropertyValue(TermuxPropertyConstants.KEY_EXTRA_KEYS_STYLE, true);
-            mExtraKeysInfo = new ExtraKeysInfo(extrakeys, extraKeysStyle);
+
+            ExtraKeysConstants.ExtraKeyDisplayMap extraKeyDisplayMap = ExtraKeysInfo.getCharDisplayMapForStyle(extraKeysStyle);
+            if (EXTRA_KEY_DISPLAY_MAPS.DEFAULT_CHAR_DISPLAY.equals(extraKeyDisplayMap) && !TermuxPropertyConstants.DEFAULT_IVALUE_EXTRA_KEYS_STYLE.equals(extraKeysStyle)) {
+                Logger.logError(TermuxSharedProperties.LOG_TAG, "The style \"" + extraKeysStyle + "\" for the key \"" + TermuxPropertyConstants.KEY_EXTRA_KEYS_STYLE + "\" is invalid. Using default style instead.");
+                extraKeysStyle = TermuxPropertyConstants.DEFAULT_IVALUE_EXTRA_KEYS_STYLE;
+            }
+
+            mExtraKeysInfo = new ExtraKeysInfo(extrakeys, extraKeysStyle, ExtraKeysConstants.CONTROL_CHARS_ALIASES);
         } catch (JSONException e) {
             Logger.showToast(mContext, "Could not load and set the \"" + TermuxPropertyConstants.KEY_EXTRA_KEYS + "\" property from the properties file: " + e.toString(), true);
             Logger.logStackTraceWithMessage(LOG_TAG, "Could not load and set the \"" + TermuxPropertyConstants.KEY_EXTRA_KEYS + "\" property from the properties file: ", e);
 
             try {
-                mExtraKeysInfo = new ExtraKeysInfo(TermuxPropertyConstants.DEFAULT_IVALUE_EXTRA_KEYS, TermuxPropertyConstants.DEFAULT_IVALUE_EXTRA_KEYS_STYLE);
+                mExtraKeysInfo = new ExtraKeysInfo(TermuxPropertyConstants.DEFAULT_IVALUE_EXTRA_KEYS, TermuxPropertyConstants.DEFAULT_IVALUE_EXTRA_KEYS_STYLE, ExtraKeysConstants.CONTROL_CHARS_ALIASES);
             } catch (JSONException e2) {
                 Logger.showToast(mContext, "Can't create default extra keys",true);
                 Logger.logStackTraceWithMessage(LOG_TAG, "Could create default extra keys: ", e);
diff --git a/app/src/main/java/com/termux/app/terminal/TermuxTerminalViewClient.java b/app/src/main/java/com/termux/app/terminal/TermuxTerminalViewClient.java
index 7e68d3ecf3..8e720444bc 100644
--- a/app/src/main/java/com/termux/app/terminal/TermuxTerminalViewClient.java
+++ b/app/src/main/java/com/termux/app/terminal/TermuxTerminalViewClient.java
@@ -27,13 +27,13 @@
 import com.termux.shared.interact.MessageDialogUtils;
 import com.termux.shared.shell.ShellUtils;
 import com.termux.shared.terminal.TermuxTerminalViewClientBase;
+import com.termux.shared.terminal.io.extrakeys.SpecialButton;
 import com.termux.shared.termux.AndroidUtils;
 import com.termux.shared.termux.TermuxConstants;
 import com.termux.shared.activities.ReportActivity;
 import com.termux.shared.models.ReportInfo;
 import com.termux.app.models.UserAction;
 import com.termux.app.terminal.io.KeyboardShortcut;
-import com.termux.app.terminal.io.extrakeys.ExtraKeysView;
 import com.termux.shared.settings.properties.TermuxPropertyConstants;
 import com.termux.shared.data.DataUtils;
 import com.termux.shared.logger.Logger;
@@ -289,12 +289,22 @@ private boolean handleVirtualKeys(int keyCode, KeyEvent event, boolean down) {
 
     @Override
     public boolean readControlKey() {
-        return (mActivity.getExtraKeysView() != null && mActivity.getExtraKeysView().readSpecialButton(ExtraKeysView.SpecialButton.CTRL)) || mVirtualControlKeyDown;
+        return readExtraKeysSpecialButton(SpecialButton.CTRL) || mVirtualControlKeyDown;
     }
 
     @Override
     public boolean readAltKey() {
-        return (mActivity.getExtraKeysView() != null && mActivity.getExtraKeysView().readSpecialButton(ExtraKeysView.SpecialButton.ALT));
+        return readExtraKeysSpecialButton(SpecialButton.ALT);
+    }
+
+    public boolean readExtraKeysSpecialButton(SpecialButton specialButton) {
+        if (mActivity.getExtraKeysView() == null) return false;
+        Boolean state = mActivity.getExtraKeysView().readSpecialButton(specialButton, true);
+        if (state == null) {
+            Logger.logError(LOG_TAG,"Failed to read an unregistered " + specialButton + " special button value from extra keys.");
+            return false;
+        }
+        return state;
     }
 
     @Override
diff --git a/app/src/main/java/com/termux/app/terminal/io/TerminalToolbarViewPager.java b/app/src/main/java/com/termux/app/terminal/io/TerminalToolbarViewPager.java
index dc306852b2..56f28fc0c2 100644
--- a/app/src/main/java/com/termux/app/terminal/io/TerminalToolbarViewPager.java
+++ b/app/src/main/java/com/termux/app/terminal/io/TerminalToolbarViewPager.java
@@ -11,7 +11,7 @@
 
 import com.termux.R;
 import com.termux.app.TermuxActivity;
-import com.termux.app.terminal.io.extrakeys.ExtraKeysView;
+import com.termux.shared.terminal.io.extrakeys.ExtraKeysView;
 import com.termux.terminal.TerminalSession;
 
 public class TerminalToolbarViewPager {
@@ -44,8 +44,8 @@ public Object instantiateItem(@NonNull ViewGroup collection, int position) {
             if (position == 0) {
                 layout = inflater.inflate(R.layout.view_terminal_toolbar_extra_keys, collection, false);
                 ExtraKeysView extraKeysView = (ExtraKeysView) layout;
-                extraKeysView.setTermuxTerminalViewClient(mActivity.getTermuxTerminalViewClient());
-                extraKeysView.setTermuxTerminalSessionClient(mActivity.getTermuxTerminalSessionClient());
+                extraKeysView.setExtraKeysViewClient(new TermuxTerminalExtraKeys(mActivity.getTerminalView(),
+                    mActivity.getTermuxTerminalViewClient(), mActivity.getTermuxTerminalSessionClient()));
                 mActivity.setExtraKeysView(extraKeysView);
                 extraKeysView.reload(mActivity.getProperties().getExtraKeysInfo());
 
diff --git a/app/src/main/java/com/termux/app/terminal/io/TermuxTerminalExtraKeys.java b/app/src/main/java/com/termux/app/terminal/io/TermuxTerminalExtraKeys.java
new file mode 100644
index 0000000000..483e6c0f2e
--- /dev/null
+++ b/app/src/main/java/com/termux/app/terminal/io/TermuxTerminalExtraKeys.java
@@ -0,0 +1,47 @@
+package com.termux.app.terminal.io;
+
+import android.annotation.SuppressLint;
+import android.view.Gravity;
+import android.view.View;
+
+import androidx.annotation.NonNull;
+import androidx.drawerlayout.widget.DrawerLayout;
+
+import com.termux.R;
+import com.termux.app.terminal.TermuxTerminalSessionClient;
+import com.termux.app.terminal.TermuxTerminalViewClient;
+import com.termux.shared.terminal.io.TerminalExtraKeys;
+import com.termux.view.TerminalView;
+
+public class TermuxTerminalExtraKeys extends TerminalExtraKeys {
+
+
+    TermuxTerminalViewClient mTermuxTerminalViewClient;
+    TermuxTerminalSessionClient mTermuxTerminalSessionClient;
+
+    public TermuxTerminalExtraKeys(@NonNull TerminalView terminalView,
+                                   TermuxTerminalViewClient termuxTerminalViewClient,
+                                   TermuxTerminalSessionClient termuxTerminalSessionClient) {
+        super(terminalView);
+        mTermuxTerminalViewClient = termuxTerminalViewClient;
+        mTermuxTerminalSessionClient = termuxTerminalSessionClient;
+    }
+
+    @SuppressLint("RtlHardcoded")
+    @Override
+    public void onTerminalExtraKeyButtonClick(View view, String key, boolean ctrlDown, boolean altDown, boolean shiftDown, boolean fnDown) {
+        if ("KEYBOARD".equals(key)) {
+            if(mTermuxTerminalViewClient != null)
+                mTermuxTerminalViewClient.onToggleSoftKeyboardRequest();
+        } else if ("DRAWER".equals(key)) {
+            DrawerLayout drawer = view.findViewById(R.id.drawer_layout);
+            drawer.openDrawer(Gravity.LEFT);
+        } else if ("PASTE".equals(key)) {
+            if(mTermuxTerminalSessionClient != null)
+                mTermuxTerminalSessionClient.onPasteTextFromClipboard(null);
+        } else {
+            super.onTerminalExtraKeyButtonClick(view, key, ctrlDown, altDown, shiftDown, fnDown);
+        }
+    }
+
+}
diff --git a/app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeyButton.java b/app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeyButton.java
deleted file mode 100644
index 9454081970..0000000000
--- a/app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeyButton.java
+++ /dev/null
@@ -1,92 +0,0 @@
-package com.termux.app.terminal.io.extrakeys;
-
-import android.text.TextUtils;
-
-import androidx.annotation.Nullable;
-
-import org.json.JSONException;
-import org.json.JSONObject;
-
-import java.util.Arrays;
-import java.util.stream.Collectors;
-
-public class ExtraKeyButton {
-
-    /**
-     * The key that will be sent to the terminal, either a control character
-     * defined in ExtraKeysView.keyCodesForString (LEFT, RIGHT, PGUP...) or
-     * some text.
-     */
-    private final String key;
-
-    /**
-     * If the key is a macro, i.e. a sequence of keys separated by space.
-     */
-    private final boolean macro;
-
-    /**
-     * The text that will be shown on the button.
-     */
-    private final String display;
-
-    /**
-     * The information of the popup (triggered by swipe up).
-     */
-    @Nullable
-    private ExtraKeyButton popup;
-
-    public ExtraKeyButton(ExtraKeysInfo.CharDisplayMap charDisplayMap, JSONObject config) throws JSONException {
-        this(charDisplayMap, config, null);
-    }
-
-    public ExtraKeyButton(ExtraKeysInfo.CharDisplayMap charDisplayMap, JSONObject config, @Nullable ExtraKeyButton popup) throws JSONException {
-        String keyFromConfig = config.optString("key", null);
-        String macroFromConfig = config.optString("macro", null);
-        String[] keys;
-        if (keyFromConfig != null && macroFromConfig != null) {
-            throw new JSONException("Both key and macro can't be set for the same key");
-        } else if (keyFromConfig != null) {
-            keys = new String[]{keyFromConfig};
-            this.macro = false;
-        } else if (macroFromConfig != null) {
-            keys = macroFromConfig.split(" ");
-            this.macro = true;
-        } else {
-            throw new JSONException("All keys have to specify either key or macro");
-        }
-
-        for (int i = 0; i < keys.length; i++) {
-            keys[i] = ExtraKeysInfo.replaceAlias(keys[i]);
-        }
-
-        this.key = TextUtils.join(" ", keys);
-
-        String displayFromConfig = config.optString("display", null);
-        if (displayFromConfig != null) {
-            this.display = displayFromConfig;
-        } else {
-            this.display = Arrays.stream(keys)
-                .map(key -> charDisplayMap.get(key, key))
-                .collect(Collectors.joining(" "));
-        }
-
-        this.popup = popup;
-    }
-
-    public String getKey() {
-        return key;
-    }
-
-    public boolean isMacro() {
-        return macro;
-    }
-
-    public String getDisplay() {
-        return display;
-    }
-
-    @Nullable
-    public ExtraKeyButton getPopup() {
-        return popup;
-    }
-}
diff --git a/app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeysInfo.java b/app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeysInfo.java
deleted file mode 100644
index ceaad78739..0000000000
--- a/app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeysInfo.java
+++ /dev/null
@@ -1,260 +0,0 @@
-package com.termux.app.terminal.io.extrakeys;
-
-import com.termux.shared.logger.Logger;
-import com.termux.shared.settings.properties.TermuxPropertyConstants;
-import com.termux.shared.settings.properties.TermuxSharedProperties;
-
-import org.json.JSONArray;
-import org.json.JSONException;
-import org.json.JSONObject;
-
-import java.util.HashMap;
-
-public class ExtraKeysInfo {
-
-    /**
-     * Matrix of buttons displayed
-     */
-    private final ExtraKeyButton[][] buttons;
-
-    /**
-     * This corresponds to one of the CharMapDisplay below
-     */
-    private String style;
-
-    public ExtraKeysInfo(String propertiesInfo, String style) throws JSONException {
-        this.style = style;
-
-        // Convert String propertiesInfo to Array of Arrays
-        JSONArray arr = new JSONArray(propertiesInfo);
-        Object[][] matrix = new Object[arr.length()][];
-        for (int i = 0; i < arr.length(); i++) {
-            JSONArray line = arr.getJSONArray(i);
-            matrix[i] = new Object[line.length()];
-            for (int j = 0; j < line.length(); j++) {
-                matrix[i][j] = line.get(j);
-            }
-        }
-
-        // convert matrix to buttons
-        this.buttons = new ExtraKeyButton[matrix.length][];
-        for (int i = 0; i < matrix.length; i++) {
-            this.buttons[i] = new ExtraKeyButton[matrix[i].length];
-            for (int j = 0; j < matrix[i].length; j++) {
-                Object key = matrix[i][j];
-
-                JSONObject jobject = normalizeKeyConfig(key);
-
-                ExtraKeyButton button;
-
-                if (! jobject.has("popup")) {
-                    // no popup
-                    button = new ExtraKeyButton(getSelectedCharMap(), jobject);
-                } else {
-                    // a popup
-                    JSONObject popupJobject = normalizeKeyConfig(jobject.get("popup"));
-                    ExtraKeyButton popup = new ExtraKeyButton(getSelectedCharMap(), popupJobject);
-                    button = new ExtraKeyButton(getSelectedCharMap(), jobject, popup);
-                }
-
-                this.buttons[i][j] = button;
-            }
-        }
-    }
-
-    /**
-     * "hello" -> {"key": "hello"}
-     */
-    private static JSONObject normalizeKeyConfig(Object key) throws JSONException {
-        JSONObject jobject;
-        if (key instanceof String) {
-            jobject = new JSONObject();
-            jobject.put("key", key);
-        } else if (key instanceof JSONObject) {
-            jobject = (JSONObject) key;
-        } else {
-            throw new JSONException("An key in the extra-key matrix must be a string or an object");
-        }
-        return jobject;
-    }
-
-    public ExtraKeyButton[][] getMatrix() {
-        return buttons;
-    }
-
-    /**
-     * HashMap that implements Python dict.get(key, default) function.
-     * Default java.util .get(key) is then the same as .get(key, null);
-     */
-    static class CleverMap<K,V> extends HashMap<K,V> {
-        V get(K key, V defaultValue) {
-            if (containsKey(key))
-                return get(key);
-            else
-                return defaultValue;
-        }
-    }
-
-    static class CharDisplayMap extends CleverMap<String, String> {}
-
-    /**
-     * Keys are displayed in a natural looking way, like "→" for "RIGHT"
-     */
-    static final CharDisplayMap classicArrowsDisplay = new CharDisplayMap() {{
-        // classic arrow keys (for ◀ ▶ ▲ ▼ @see arrowVariationDisplay)
-        put("LEFT", "←"); // U+2190 ← LEFTWARDS ARROW
-        put("RIGHT", "→"); // U+2192 → RIGHTWARDS ARROW
-        put("UP", "↑"); // U+2191 ↑ UPWARDS ARROW
-        put("DOWN", "↓"); // U+2193 ↓ DOWNWARDS ARROW
-    }};
-
-    static final CharDisplayMap wellKnownCharactersDisplay = new CharDisplayMap() {{
-        // well known characters // https://en.wikipedia.org/wiki/{Enter_key, Tab_key, Delete_key}
-        put("ENTER", "↲"); // U+21B2 ↲ DOWNWARDS ARROW WITH TIP LEFTWARDS
-        put("TAB", "↹"); // U+21B9 ↹ LEFTWARDS ARROW TO BAR OVER RIGHTWARDS ARROW TO BAR
-        put("BKSP", "⌫"); // U+232B ⌫ ERASE TO THE LEFT sometimes seen and easy to understand
-        put("DEL", "⌦"); // U+2326 ⌦ ERASE TO THE RIGHT not well known but easy to understand
-        put("DRAWER", "☰"); // U+2630 ☰ TRIGRAM FOR HEAVEN not well known but easy to understand
-        put("KEYBOARD", "⌨"); // U+2328 ⌨ KEYBOARD not well known but easy to understand
-        put("PASTE", "⎘"); // U+2398
-    }};
-
-    static final CharDisplayMap lessKnownCharactersDisplay = new CharDisplayMap() {{
-        // https://en.wikipedia.org/wiki/{Home_key, End_key, Page_Up_and_Page_Down_keys}
-        // home key can mean "goto the beginning of line" or "goto first page" depending on context, hence the diagonal
-        put("HOME", "⇱"); // from IEC 9995 // U+21F1 ⇱ NORTH WEST ARROW TO CORNER
-        put("END", "⇲"); // from IEC 9995 // ⇲ // U+21F2 ⇲ SOUTH EAST ARROW TO CORNER
-        put("PGUP", "⇑"); // no ISO character exists, U+21D1 ⇑ UPWARDS DOUBLE ARROW will do the trick
-        put("PGDN", "⇓"); // no ISO character exists, U+21D3 ⇓ DOWNWARDS DOUBLE ARROW will do the trick
-    }};
-
-    static final CharDisplayMap arrowTriangleVariationDisplay = new CharDisplayMap() {{
-        // alternative to classic arrow keys
-        put("LEFT", "◀"); // U+25C0 ◀ BLACK LEFT-POINTING TRIANGLE
-        put("RIGHT", "▶"); // U+25B6 ▶ BLACK RIGHT-POINTING TRIANGLE
-        put("UP", "▲"); // U+25B2 ▲ BLACK UP-POINTING TRIANGLE
-        put("DOWN", "▼"); // U+25BC ▼ BLACK DOWN-POINTING TRIANGLE
-    }};
-
-    static final CharDisplayMap notKnownIsoCharacters = new CharDisplayMap() {{
-        // Control chars that are more clear as text // https://en.wikipedia.org/wiki/{Function_key, Alt_key, Control_key, Esc_key}
-        // put("FN", "FN"); // no ISO character exists
-        put("CTRL", "⎈"); // ISO character "U+2388 ⎈ HELM SYMBOL" is unknown to people and never printed on computers, however "U+25C7 ◇ WHITE DIAMOND" is a nice presentation, and "^" for terminal app and mac is often used
-        put("ALT", "⎇"); // ISO character "U+2387 ⎇ ALTERNATIVE KEY SYMBOL'" is unknown to people and only printed as the Option key "⌥" on Mac computer
-        put("ESC", "⎋"); // ISO character "U+238B ⎋ BROKEN CIRCLE WITH NORTHWEST ARROW" is unknown to people and not often printed on computers
-    }};
-
-    static final CharDisplayMap nicerLookingDisplay = new CharDisplayMap() {{
-        // nicer looking for most cases
-        put("-", "―"); // U+2015 ― HORIZONTAL BAR
-    }};
-
-    /*
-     * Multiple maps are available to quickly change
-     * the style of the keys.
-     */
-
-    /**
-     * Some classic symbols everybody knows
-     */
-    private static final CharDisplayMap defaultCharDisplay = new CharDisplayMap() {{
-        putAll(classicArrowsDisplay);
-        putAll(wellKnownCharactersDisplay);
-        putAll(nicerLookingDisplay);
-        // all other characters are displayed as themselves
-    }};
-
-    /**
-     * Classic symbols and less known symbols
-     */
-    private static final CharDisplayMap lotsOfArrowsCharDisplay = new CharDisplayMap() {{
-        putAll(classicArrowsDisplay);
-        putAll(wellKnownCharactersDisplay);
-        putAll(lessKnownCharactersDisplay); // NEW
-        putAll(nicerLookingDisplay);
-    }};
-
-    /**
-     * Only arrows
-     */
-    private static final CharDisplayMap arrowsOnlyCharDisplay = new CharDisplayMap() {{
-        putAll(classicArrowsDisplay);
-        // putAll(wellKnownCharactersDisplay); // REMOVED
-        // putAll(lessKnownCharactersDisplay); // REMOVED
-        putAll(nicerLookingDisplay);
-    }};
-
-    /**
-     * Full Iso
-     */
-    private static final CharDisplayMap fullIsoCharDisplay = new CharDisplayMap() {{
-        putAll(classicArrowsDisplay);
-        putAll(wellKnownCharactersDisplay);
-        putAll(lessKnownCharactersDisplay); // NEW
-        putAll(nicerLookingDisplay);
-        putAll(notKnownIsoCharacters); // NEW
-    }};
-
-    /**
-     * Some people might call our keys differently
-     */
-    static private final CharDisplayMap controlCharsAliases = new CharDisplayMap() {{
-        put("ESCAPE", "ESC");
-        put("CONTROL", "CTRL");
-        put("RETURN", "ENTER"); // Technically different keys, but most applications won't see the difference
-        put("FUNCTION", "FN");
-        // no alias for ALT
-
-        // Directions are sometimes written as first and last letter for brevety
-        put("LT", "LEFT");
-        put("RT", "RIGHT");
-        put("DN", "DOWN");
-        // put("UP", "UP"); well, "UP" is already two letters
-
-        put("PAGEUP", "PGUP");
-        put("PAGE_UP", "PGUP");
-        put("PAGE UP", "PGUP");
-        put("PAGE-UP", "PGUP");
-
-        // no alias for HOME
-        // no alias for END
-
-        put("PAGEDOWN", "PGDN");
-        put("PAGE_DOWN", "PGDN");
-        put("PAGE-DOWN", "PGDN");
-
-        put("DELETE", "DEL");
-        put("BACKSPACE", "BKSP");
-
-        // easier for writing in termux.properties
-        put("BACKSLASH", "\\");
-        put("QUOTE", "\"");
-        put("APOSTROPHE", "'");
-    }};
-
-    CharDisplayMap getSelectedCharMap() {
-        switch (style) {
-            case "arrows-only":
-                return arrowsOnlyCharDisplay;
-            case "arrows-all":
-                return lotsOfArrowsCharDisplay;
-            case "all":
-                return fullIsoCharDisplay;
-            case "none":
-                return new CharDisplayMap();
-            default:
-                if (!TermuxPropertyConstants.DEFAULT_IVALUE_EXTRA_KEYS_STYLE.equals(style))
-                    Logger.logError(TermuxSharedProperties.LOG_TAG, "The style \"" + style + "\" for the key \"" + TermuxPropertyConstants.KEY_EXTRA_KEYS_STYLE + "\" is invalid. Using default style instead.");
-                return defaultCharDisplay;
-        }
-    }
-
-    /**
-     * Applies the 'controlCharsAliases' mapping to all the strings in *buttons*
-     * Modifies the array, doesn't return a new one.
-     */
-    public static String replaceAlias(String key) {
-        return controlCharsAliases.get(key, key);
-    }
-}
-
diff --git a/app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeysView.java b/app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeysView.java
deleted file mode 100644
index 79aceaa17d..0000000000
--- a/app/src/main/java/com/termux/app/terminal/io/extrakeys/ExtraKeysView.java
+++ /dev/null
@@ -1,401 +0,0 @@
-package com.termux.app.terminal.io.extrakeys;
-
-import android.annotation.SuppressLint;
-import android.content.Context;
-import android.os.Build;
-import android.provider.Settings;
-import android.util.AttributeSet;
-
-import java.util.ArrayList;
-import java.util.List;
-import java.util.Set;
-import java.util.concurrent.Executors;
-import java.util.concurrent.TimeUnit;
-import java.util.concurrent.ScheduledExecutorService;
-
-import java.util.Map;
-import java.util.HashMap;
-import java.util.Arrays;
-import java.util.stream.Collectors;
-
-import android.view.Gravity;
-import android.view.HapticFeedbackConstants;
-import android.view.KeyEvent;
-import android.view.MotionEvent;
-import android.view.View;
-import android.widget.Button;
-import android.widget.GridLayout;
-import android.widget.PopupWindow;
-
-import com.termux.R;
-import com.termux.app.terminal.TermuxTerminalSessionClient;
-import com.termux.app.terminal.TermuxTerminalViewClient;
-import com.termux.view.TerminalView;
-
-import androidx.drawerlayout.widget.DrawerLayout;
-
-/**
- * A view showing extra keys (such as Escape, Ctrl, Alt) not normally available on an Android soft
- * keyboard.
- */
-public final class ExtraKeysView extends GridLayout {
-
-    private static final int TEXT_COLOR = 0xFFFFFFFF;
-    private static final int BUTTON_COLOR = 0x00000000;
-    private static final int INTERESTING_COLOR = 0xFF80DEEA;
-    private static final int BUTTON_PRESSED_COLOR = 0xFF7F7F7F;
-
-    TermuxTerminalViewClient mTermuxTerminalViewClient;
-    TermuxTerminalSessionClient mTermuxTerminalSessionClient;
-
-    public ExtraKeysView(Context context, AttributeSet attrs) {
-        super(context, attrs);
-    }
-
-    static final Map<String, Integer> keyCodesForString = new HashMap<String, Integer>() {{
-        put("SPACE", KeyEvent.KEYCODE_SPACE);
-        put("ESC", KeyEvent.KEYCODE_ESCAPE);
-        put("TAB", KeyEvent.KEYCODE_TAB);
-        put("HOME", KeyEvent.KEYCODE_MOVE_HOME);
-        put("END", KeyEvent.KEYCODE_MOVE_END);
-        put("PGUP", KeyEvent.KEYCODE_PAGE_UP);
-        put("PGDN", KeyEvent.KEYCODE_PAGE_DOWN);
-        put("INS", KeyEvent.KEYCODE_INSERT);
-        put("DEL", KeyEvent.KEYCODE_FORWARD_DEL);
-        put("BKSP", KeyEvent.KEYCODE_DEL);
-        put("UP", KeyEvent.KEYCODE_DPAD_UP);
-        put("LEFT", KeyEvent.KEYCODE_DPAD_LEFT);
-        put("RIGHT", KeyEvent.KEYCODE_DPAD_RIGHT);
-        put("DOWN", KeyEvent.KEYCODE_DPAD_DOWN);
-        put("ENTER", KeyEvent.KEYCODE_ENTER);
-        put("F1", KeyEvent.KEYCODE_F1);
-        put("F2", KeyEvent.KEYCODE_F2);
-        put("F3", KeyEvent.KEYCODE_F3);
-        put("F4", KeyEvent.KEYCODE_F4);
-        put("F5", KeyEvent.KEYCODE_F5);
-        put("F6", KeyEvent.KEYCODE_F6);
-        put("F7", KeyEvent.KEYCODE_F7);
-        put("F8", KeyEvent.KEYCODE_F8);
-        put("F9", KeyEvent.KEYCODE_F9);
-        put("F10", KeyEvent.KEYCODE_F10);
-        put("F11", KeyEvent.KEYCODE_F11);
-        put("F12", KeyEvent.KEYCODE_F12);
-    }};
-
-    @SuppressLint("RtlHardcoded")
-    private void sendKey(View view, String keyName, boolean forceCtrlDown, boolean forceLeftAltDown) {
-        TerminalView terminalView = view.findViewById(R.id.terminal_view);
-        if ("KEYBOARD".equals(keyName)) {
-            if(mTermuxTerminalViewClient != null)
-                mTermuxTerminalViewClient.onToggleSoftKeyboardRequest();
-        } else if ("DRAWER".equals(keyName)) {
-            DrawerLayout drawer = view.findViewById(R.id.drawer_layout);
-            drawer.openDrawer(Gravity.LEFT);
-        } else if ("PASTE".equals(keyName)) {
-            if(mTermuxTerminalSessionClient != null)
-                mTermuxTerminalSessionClient.onPasteTextFromClipboard(null);
-        } else if (keyCodesForString.containsKey(keyName)) {
-            Integer keyCode = keyCodesForString.get(keyName);
-            if (keyCode == null) return;
-            int metaState = 0;
-            if (forceCtrlDown) {
-                metaState |= KeyEvent.META_CTRL_ON | KeyEvent.META_CTRL_LEFT_ON;
-            }
-            if (forceLeftAltDown) {
-                metaState |= KeyEvent.META_ALT_ON | KeyEvent.META_ALT_LEFT_ON;
-            }
-            KeyEvent keyEvent = new KeyEvent(0, 0, KeyEvent.ACTION_UP, keyCode, 0, metaState);
-            terminalView.onKeyDown(keyCode, keyEvent);
-        } else {
-            // not a control char
-            keyName.codePoints().forEach(codePoint -> {
-                terminalView.inputCodePoint(codePoint, forceCtrlDown, forceLeftAltDown);
-            });
-        }
-    }
-
-    private void sendKey(View view, ExtraKeyButton buttonInfo) {
-        if (buttonInfo.isMacro()) {
-            String[] keys = buttonInfo.getKey().split(" ");
-            boolean ctrlDown = false;
-            boolean altDown = false;
-            for (String key : keys) {
-                if ("CTRL".equals(key)) {
-                    ctrlDown = true;
-                } else if ("ALT".equals(key)) {
-                    altDown = true;
-                } else {
-                    sendKey(view, key, ctrlDown, altDown);
-                    ctrlDown = false;
-                    altDown = false;
-                }
-            }
-        } else {
-            sendKey(view, buttonInfo.getKey(), false, false);
-        }
-    }
-
-    public enum SpecialButton {
-        CTRL, ALT, FN
-    }
-
-    private static class SpecialButtonState {
-        boolean isOn = false;
-        boolean isActive = false;
-        List<Button> buttons = new ArrayList<>();
-
-        void setIsActive(boolean value) {
-            isActive = value;
-            buttons.forEach(button -> button.setTextColor(value ? INTERESTING_COLOR : TEXT_COLOR));
-        }
-    }
-
-    private final Map<SpecialButton, SpecialButtonState> specialButtons = new HashMap<SpecialButton, SpecialButtonState>() {{
-        put(SpecialButton.CTRL, new SpecialButtonState());
-        put(SpecialButton.ALT, new SpecialButtonState());
-        put(SpecialButton.FN, new SpecialButtonState());
-    }};
-
-    private final Set<String> specialButtonsKeys = specialButtons.keySet().stream().map(Enum::name).collect(Collectors.toSet());
-
-    private boolean isSpecialButton(ExtraKeyButton button) {
-        return specialButtonsKeys.contains(button.getKey());
-    }
-
-    private ScheduledExecutorService scheduledExecutor;
-    private PopupWindow popupWindow;
-    private int longPressCount;
-
-    public boolean readSpecialButton(SpecialButton name) {
-        SpecialButtonState state = specialButtons.get(name);
-        if (state == null)
-            throw new RuntimeException("Must be a valid special button (see source)");
-
-        if (!state.isOn || !state.isActive)
-            return false;
-
-        state.setIsActive(false);
-
-        return true;
-    }
-
-    private Button createSpecialButton(String buttonKey, boolean needUpdate) {
-        SpecialButtonState state = specialButtons.get(SpecialButton.valueOf(buttonKey));
-        if (state == null) return null;
-        state.isOn = true;
-        Button button = new Button(getContext(), null, android.R.attr.buttonBarButtonStyle);
-        button.setTextColor(state.isActive ? INTERESTING_COLOR : TEXT_COLOR);
-        if (needUpdate) {
-            state.buttons.add(button);
-        }
-        return button;
-    }
-
-    void popup(View view, ExtraKeyButton extraButton) {
-        int width = view.getMeasuredWidth();
-        int height = view.getMeasuredHeight();
-        Button button;
-        if (isSpecialButton(extraButton)) {
-            button = createSpecialButton(extraButton.getKey(), false);
-            if (button == null) return;
-        } else {
-            button = new Button(getContext(), null, android.R.attr.buttonBarButtonStyle);
-            button.setTextColor(TEXT_COLOR);
-        }
-        button.setText(extraButton.getDisplay());
-        button.setPadding(0, 0, 0, 0);
-        button.setMinHeight(0);
-        button.setMinWidth(0);
-        button.setMinimumWidth(0);
-        button.setMinimumHeight(0);
-        button.setWidth(width);
-        button.setHeight(height);
-        button.setBackgroundColor(BUTTON_PRESSED_COLOR);
-        popupWindow = new PopupWindow(this);
-        popupWindow.setWidth(LayoutParams.WRAP_CONTENT);
-        popupWindow.setHeight(LayoutParams.WRAP_CONTENT);
-        popupWindow.setContentView(button);
-        popupWindow.setOutsideTouchable(true);
-        popupWindow.setFocusable(false);
-        popupWindow.showAsDropDown(view, 0, -2 * height);
-    }
-
-    /**
-     * General util function to compute the longest column length in a matrix.
-     */
-    static int maximumLength(Object[][] matrix) {
-        int m = 0;
-        for (Object[] row : matrix)
-            m = Math.max(m, row.length);
-        return m;
-    }
-
-    /**
-     * Reload the view given parameters in termux.properties
-     *
-     * @param infos matrix as defined in termux.properties extrakeys
-     * Can Contain The Strings CTRL ALT TAB FN ENTER LEFT RIGHT UP DOWN or normal strings
-     * Some aliases are possible like RETURN for ENTER, LT for LEFT and more (@see controlCharsAliases for the whole list).
-     * Any string of length > 1 in total Uppercase will print a warning
-     *
-     * Examples:
-     * "ENTER" will trigger the ENTER keycode
-     * "LEFT" will trigger the LEFT keycode and be displayed as "←"
-     * "→" will input a "→" character
-     * "−" will input a "−" character
-     * "-_-" will input the string "-_-"
-     */
-    @SuppressLint("ClickableViewAccessibility")
-    public void reload(ExtraKeysInfo infos) {
-        if (infos == null)
-            return;
-
-        for(SpecialButtonState state : specialButtons.values())
-            state.buttons = new ArrayList<>();
-
-        removeAllViews();
-
-        ExtraKeyButton[][] buttons = infos.getMatrix();
-
-        setRowCount(buttons.length);
-        setColumnCount(maximumLength(buttons));
-
-        for (int row = 0; row < buttons.length; row++) {
-            for (int col = 0; col < buttons[row].length; col++) {
-                final ExtraKeyButton buttonInfo = buttons[row][col];
-
-                Button button;
-                if (isSpecialButton(buttonInfo)) {
-                    button = createSpecialButton(buttonInfo.getKey(), true);
-                    if (button == null) return;
-                } else {
-                    button = new Button(getContext(), null, android.R.attr.buttonBarButtonStyle);
-                }
-
-                button.setText(buttonInfo.getDisplay());
-                button.setTextColor(TEXT_COLOR);
-                button.setPadding(0, 0, 0, 0);
-
-                final Button finalButton = button;
-                button.setOnClickListener(v -> {
-                    if (Settings.System.getInt(getContext().getContentResolver(),
-                        Settings.System.HAPTIC_FEEDBACK_ENABLED, 0) != 0) {
-
-                        if (Build.VERSION.SDK_INT >= 28) {
-                            finalButton.performHapticFeedback(HapticFeedbackConstants.KEYBOARD_TAP);
-                        } else {
-                            // Perform haptic feedback only if no total silence mode enabled.
-                            if (Settings.Global.getInt(getContext().getContentResolver(), "zen_mode", 0) != 2) {
-                                finalButton.performHapticFeedback(HapticFeedbackConstants.KEYBOARD_TAP);
-                            }
-                        }
-                    }
-
-                    View root = getRootView();
-                    if (isSpecialButton(buttonInfo)) {
-                        SpecialButtonState state = specialButtons.get(SpecialButton.valueOf(buttonInfo.getKey()));
-                        if (state == null) return;
-                        state.setIsActive(!state.isActive);
-                    } else {
-                        sendKey(root, buttonInfo);
-                    }
-                });
-
-                button.setOnTouchListener((v, event) -> {
-                    final View root = getRootView();
-                    switch (event.getAction()) {
-                        case MotionEvent.ACTION_DOWN:
-                            longPressCount = 0;
-                            v.setBackgroundColor(BUTTON_PRESSED_COLOR);
-                            if (scheduledExecutor != null) {
-                                scheduledExecutor.shutdownNow();
-                                scheduledExecutor = null;
-                            }
-                            if (Arrays.asList("UP", "DOWN", "LEFT", "RIGHT", "BKSP", "DEL").contains(buttonInfo.getKey())) {
-                                // autorepeat
-                                scheduledExecutor = Executors.newSingleThreadScheduledExecutor();
-                                scheduledExecutor.scheduleWithFixedDelay(() -> {
-                                    longPressCount++;
-                                    sendKey(root, buttonInfo);
-                                }, 400, 80, TimeUnit.MILLISECONDS);
-                            }
-                            return true;
-
-                        case MotionEvent.ACTION_MOVE:
-                            if (buttonInfo.getPopup() != null) {
-                                if (popupWindow == null && event.getY() < 0) {
-                                    if (scheduledExecutor != null) {
-                                        scheduledExecutor.shutdownNow();
-                                        scheduledExecutor = null;
-                                    }
-                                    v.setBackgroundColor(BUTTON_COLOR);
-                                    popup(v, buttonInfo.getPopup());
-                                }
-                                if (popupWindow != null && event.getY() > 0) {
-                                    v.setBackgroundColor(BUTTON_PRESSED_COLOR);
-                                    popupWindow.dismiss();
-                                    popupWindow = null;
-                                }
-                            }
-                            return true;
-
-                        case MotionEvent.ACTION_CANCEL:
-                            v.setBackgroundColor(BUTTON_COLOR);
-                            if (scheduledExecutor != null) {
-                                scheduledExecutor.shutdownNow();
-                                scheduledExecutor = null;
-                            }
-                            return true;
-                        case MotionEvent.ACTION_UP:
-                            v.setBackgroundColor(BUTTON_COLOR);
-                            if (scheduledExecutor != null) {
-                                scheduledExecutor.shutdownNow();
-                                scheduledExecutor = null;
-                            }
-                            if (longPressCount == 0 || popupWindow != null) {
-                                if (popupWindow != null) {
-                                    popupWindow.setContentView(null);
-                                    popupWindow.dismiss();
-                                    popupWindow = null;
-                                    if (buttonInfo.getPopup() != null) {
-                                        if (isSpecialButton(buttonInfo.getPopup())) {
-                                            SpecialButtonState state = specialButtons.get(SpecialButton.valueOf(buttonInfo.getPopup().getKey()));
-                                            if (state == null) return true;
-                                            state.setIsActive(!state.isActive);
-                                        } else {
-                                            sendKey(root, buttonInfo.getPopup());
-                                        }
-                                    }
-                                } else {
-                                    v.performClick();
-                                }
-                            }
-                            return true;
-
-                        default:
-                            return true;
-                    }
-                });
-
-                LayoutParams param = new GridLayout.LayoutParams();
-                param.width = 0;
-                param.height = 0;
-                param.setMargins(0, 0, 0, 0);
-                param.columnSpec = GridLayout.spec(col, GridLayout.FILL, 1.f);
-                param.rowSpec = GridLayout.spec(row, GridLayout.FILL, 1.f);
-                button.setLayoutParams(param);
-
-                addView(button);
-            }
-        }
-    }
-
-    public void setTermuxTerminalViewClient(TermuxTerminalViewClient termuxTerminalViewClient) {
-        this.mTermuxTerminalViewClient = termuxTerminalViewClient;
-    }
-
-    public void setTermuxTerminalSessionClient(TermuxTerminalSessionClient termuxTerminalSessionClient) {
-        this.mTermuxTerminalSessionClient = termuxTerminalSessionClient;
-    }
-
-}
diff --git a/app/src/main/res/layout/view_terminal_toolbar_extra_keys.xml b/app/src/main/res/layout/view_terminal_toolbar_extra_keys.xml
index fbefe1ec6e..21a25c8100 100644
--- a/app/src/main/res/layout/view_terminal_toolbar_extra_keys.xml
+++ b/app/src/main/res/layout/view_terminal_toolbar_extra_keys.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<com.termux.app.terminal.io.extrakeys.ExtraKeysView xmlns:android="http://schemas.android.com/apk/res/android"
+<com.termux.shared.terminal.io.extrakeys.ExtraKeysView xmlns:android="http://schemas.android.com/apk/res/android"
     android:id="@+id/terminal_toolbar_extra_keys"
     style="?android:attr/buttonBarStyle"
     android:layout_width="match_parent"
diff --git a/termux-shared/src/main/java/com/termux/shared/terminal/io/TerminalExtraKeys.java b/termux-shared/src/main/java/com/termux/shared/terminal/io/TerminalExtraKeys.java
new file mode 100644
index 0000000000..faac49771d
--- /dev/null
+++ b/termux-shared/src/main/java/com/termux/shared/terminal/io/TerminalExtraKeys.java
@@ -0,0 +1,77 @@
+package com.termux.shared.terminal.io;
+
+import android.view.KeyEvent;
+import android.view.View;
+import android.widget.Button;
+
+import androidx.annotation.NonNull;
+
+import com.termux.shared.terminal.io.extrakeys.ExtraKeyButton;
+import com.termux.shared.terminal.io.extrakeys.ExtraKeysView;
+import com.termux.shared.terminal.io.extrakeys.SpecialButton;
+import com.termux.view.TerminalView;
+
+import static com.termux.shared.terminal.io.extrakeys.ExtraKeysConstants.PRIMARY_KEY_CODES_FOR_STRINGS;
+
+
+public class TerminalExtraKeys implements ExtraKeysView.IExtraKeysView {
+
+    private final TerminalView mTerminalView;
+
+    public TerminalExtraKeys(@NonNull TerminalView terminalView) {
+        mTerminalView = terminalView;
+    }
+
+    @Override
+    public void onExtraKeyButtonClick(View view, ExtraKeyButton buttonInfo, Button button) {
+        if (buttonInfo.isMacro()) {
+            String[] keys = buttonInfo.getKey().split(" ");
+            boolean ctrlDown = false;
+            boolean altDown = false;
+            boolean shiftDown = false;
+            boolean fnDown = false;
+            for (String key : keys) {
+                if (SpecialButton.CTRL.getKey().equals(key)) {
+                    ctrlDown = true;
+                } else if (SpecialButton.ALT.getKey().equals(key)) {
+                    altDown = true;
+                } else if (SpecialButton.SHIFT.getKey().equals(key)) {
+                    shiftDown = true;
+                } else if (SpecialButton.FN.getKey().equals(key)) {
+                    fnDown = true;
+                } else {
+                    onTerminalExtraKeyButtonClick(view, key, ctrlDown, altDown, shiftDown, fnDown);
+                    ctrlDown = false; altDown = false; shiftDown = false; fnDown = false;
+                }
+            }
+        } else {
+            onTerminalExtraKeyButtonClick(view, buttonInfo.getKey(), false, false, false, false);
+        }
+    }
+
+    protected void onTerminalExtraKeyButtonClick(View view, String key, boolean ctrlDown, boolean altDown, boolean shiftDown, boolean fnDown) {
+        if (PRIMARY_KEY_CODES_FOR_STRINGS.containsKey(key)) {
+            Integer keyCode = PRIMARY_KEY_CODES_FOR_STRINGS.get(key);
+            if (keyCode == null) return;
+            int metaState = 0;
+            if (ctrlDown) metaState |= KeyEvent.META_CTRL_ON | KeyEvent.META_CTRL_LEFT_ON;
+            if (altDown) metaState |= KeyEvent.META_ALT_ON | KeyEvent.META_ALT_LEFT_ON;
+            if (shiftDown) metaState |= KeyEvent.META_SHIFT_ON | KeyEvent.META_SHIFT_LEFT_ON;
+            if (fnDown) metaState |= KeyEvent.META_FUNCTION_ON;
+
+            KeyEvent keyEvent = new KeyEvent(0, 0, KeyEvent.ACTION_UP, keyCode, 0, metaState);
+            mTerminalView.onKeyDown(keyCode, keyEvent);
+        } else {
+            // not a control char
+            key.codePoints().forEach(codePoint -> {
+                mTerminalView.inputCodePoint(codePoint, ctrlDown, altDown);
+            });
+        }
+    }
+
+    @Override
+    public boolean performExtraKeyButtonHapticFeedback(View view, ExtraKeyButton buttonInfo, Button button) {
+        return false;
+    }
+
+}
diff --git a/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeyButton.java b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeyButton.java
new file mode 100644
index 0000000000..e22879857c
--- /dev/null
+++ b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeyButton.java
@@ -0,0 +1,151 @@
+package com.termux.shared.terminal.io.extrakeys;
+
+import android.text.TextUtils;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.util.Arrays;
+import java.util.stream.Collectors;
+
+public class ExtraKeyButton {
+
+    /** The key name for the name of the extra key if using a dict to define the extra key. {key: name, ...} */
+    public static final String KEY_KEY_NAME = "key";
+
+    /** The key name for the macro value of the extra key if using a dict to define the extra key. {macro: value, ...} */
+    public static final String KEY_MACRO = "macro";
+
+    /** The key name for the alternate display name of the extra key if using a dict to define the extra key. {display: name, ...} */
+    public static final String KEY_DISPLAY_NAME = "display";
+
+    /** The key name for the nested dict to define popup extra key info if using a dict to define the extra key. {popup: {key: name, ...}, ...} */
+    public static final String KEY_POPUP = "popup";
+
+
+    /**
+     * The key that will be sent to the terminal, either a control character, like defined in
+     * {@link ExtraKeysConstants#PRIMARY_KEY_CODES_FOR_STRINGS} (LEFT, RIGHT, PGUP...) or some text.
+     */
+    private final String key;
+
+    /**
+     * If the key is a macro, i.e. a sequence of keys separated by space.
+     */
+    private final boolean macro;
+
+    /**
+     * The text that will be displayed on the button.
+     */
+    private final String display;
+
+    /**
+     * The {@link ExtraKeyButton} containing the information of the popup button (triggered by swipe up).
+     */
+    @Nullable
+    private final ExtraKeyButton popup;
+
+
+    /**
+     * Initialize a {@link ExtraKeyButton}.
+     *
+     * @param config The {@link JSONObject} containing the info to create the {@link ExtraKeyButton}.
+     * @param extraKeyDisplayMap The {@link ExtraKeysConstants.ExtraKeyDisplayMap} that defines the
+     *                           display text mapping for the keys if a custom value is not defined
+     *                           by {@link #KEY_DISPLAY_NAME}.
+     * @param extraKeyAliasMap The {@link ExtraKeysConstants.ExtraKeyDisplayMap} that defines the
+     *                           aliases for the actual key names.
+     */
+    public ExtraKeyButton(@NonNull JSONObject config,
+                          @NonNull ExtraKeysConstants.ExtraKeyDisplayMap extraKeyDisplayMap,
+                          @NonNull ExtraKeysConstants.ExtraKeyDisplayMap extraKeyAliasMap) throws JSONException {
+        this(config, null, extraKeyDisplayMap, extraKeyAliasMap);
+    }
+
+    /**
+     * Initialize a {@link ExtraKeyButton}.
+     *
+     * @param config The {@link JSONObject} containing the info to create the {@link ExtraKeyButton}.
+     * @param popup The {@link ExtraKeyButton} optional {@link #popup} button.
+     * @param extraKeyDisplayMap The {@link ExtraKeysConstants.ExtraKeyDisplayMap} that defines the
+     *                           display text mapping for the keys if a custom value is not defined
+     *                           by {@link #KEY_DISPLAY_NAME}.
+     * @param extraKeyAliasMap The {@link ExtraKeysConstants.ExtraKeyDisplayMap} that defines the
+     *                           aliases for the actual key names.
+     */
+    public ExtraKeyButton(@NonNull JSONObject config, @Nullable ExtraKeyButton popup,
+                          @NonNull ExtraKeysConstants.ExtraKeyDisplayMap extraKeyDisplayMap,
+                          @NonNull ExtraKeysConstants.ExtraKeyDisplayMap extraKeyAliasMap) throws JSONException {
+        String keyFromConfig = getStringFromJson(config, KEY_KEY_NAME);
+        String macroFromConfig = getStringFromJson(config, KEY_MACRO);
+        String[] keys;
+        if (keyFromConfig != null && macroFromConfig != null) {
+            throw new JSONException("Both key and macro can't be set for the same key. key: \"" + keyFromConfig + "\", macro: \"" + macroFromConfig + "\"");
+        } else if (keyFromConfig != null) {
+            keys = new String[]{keyFromConfig};
+            this.macro = false;
+        } else if (macroFromConfig != null) {
+            keys = macroFromConfig.split(" ");
+            this.macro = true;
+        } else {
+            throw new JSONException("All keys have to specify either key or macro");
+        }
+
+        for (int i = 0; i < keys.length; i++) {
+            keys[i] = replaceAlias(extraKeyAliasMap, keys[i]);
+        }
+
+        this.key = TextUtils.join(" ", keys);
+
+        String displayFromConfig = getStringFromJson(config, KEY_DISPLAY_NAME);
+        if (displayFromConfig != null) {
+            this.display = displayFromConfig;
+        } else {
+            this.display = Arrays.stream(keys)
+                .map(key -> extraKeyDisplayMap.get(key, key))
+                .collect(Collectors.joining(" "));
+        }
+
+        this.popup = popup;
+    }
+
+    public String getStringFromJson(@NonNull JSONObject config, @NonNull String key) {
+        try {
+            return config.getString(key);
+        } catch (JSONException e) {
+            return null;
+        }
+    }
+
+    /** Get {@link #key}. */
+    public String getKey() {
+        return key;
+    }
+
+    /** Check whether a {@link #macro} is defined or not. */
+    public boolean isMacro() {
+        return macro;
+    }
+
+    /** Get {@link #display}. */
+    public String getDisplay() {
+        return display;
+    }
+
+    /** Get {@link #popup}. */
+    @Nullable
+    public ExtraKeyButton getPopup() {
+        return popup;
+    }
+
+    /**
+     * Replace the alias with its actual key name if found in extraKeyAliasMap.
+     */
+    public static String replaceAlias(@NonNull ExtraKeysConstants.ExtraKeyDisplayMap extraKeyAliasMap, String key) {
+        return extraKeyAliasMap.get(key, key);
+    }
+
+}
diff --git a/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysConstants.java b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysConstants.java
new file mode 100644
index 0000000000..ae678a71cb
--- /dev/null
+++ b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysConstants.java
@@ -0,0 +1,207 @@
+package com.termux.shared.terminal.io.extrakeys;
+
+import android.view.KeyEvent;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class ExtraKeysConstants {
+
+    /** Defines the repetitive keys that can be passed to {@link ExtraKeysView#setRepetitiveKeys(List)}. */
+    public static List<String> PRIMARY_REPETITIVE_KEYS = Arrays.asList("UP", "DOWN", "LEFT", "RIGHT", "BKSP", "DEL");
+
+
+
+    /** Defines the {@link KeyEvent} for common keys. */
+    public static Map<String, Integer> PRIMARY_KEY_CODES_FOR_STRINGS = new HashMap<String, Integer>() {{
+        put("SPACE", KeyEvent.KEYCODE_SPACE);
+        put("ESC", KeyEvent.KEYCODE_ESCAPE);
+        put("TAB", KeyEvent.KEYCODE_TAB);
+        put("HOME", KeyEvent.KEYCODE_MOVE_HOME);
+        put("END", KeyEvent.KEYCODE_MOVE_END);
+        put("PGUP", KeyEvent.KEYCODE_PAGE_UP);
+        put("PGDN", KeyEvent.KEYCODE_PAGE_DOWN);
+        put("INS", KeyEvent.KEYCODE_INSERT);
+        put("DEL", KeyEvent.KEYCODE_FORWARD_DEL);
+        put("BKSP", KeyEvent.KEYCODE_DEL);
+        put("UP", KeyEvent.KEYCODE_DPAD_UP);
+        put("LEFT", KeyEvent.KEYCODE_DPAD_LEFT);
+        put("RIGHT", KeyEvent.KEYCODE_DPAD_RIGHT);
+        put("DOWN", KeyEvent.KEYCODE_DPAD_DOWN);
+        put("ENTER", KeyEvent.KEYCODE_ENTER);
+        put("F1", KeyEvent.KEYCODE_F1);
+        put("F2", KeyEvent.KEYCODE_F2);
+        put("F3", KeyEvent.KEYCODE_F3);
+        put("F4", KeyEvent.KEYCODE_F4);
+        put("F5", KeyEvent.KEYCODE_F5);
+        put("F6", KeyEvent.KEYCODE_F6);
+        put("F7", KeyEvent.KEYCODE_F7);
+        put("F8", KeyEvent.KEYCODE_F8);
+        put("F9", KeyEvent.KEYCODE_F9);
+        put("F10", KeyEvent.KEYCODE_F10);
+        put("F11", KeyEvent.KEYCODE_F11);
+        put("F12", KeyEvent.KEYCODE_F12);
+    }};
+
+
+
+    /**
+     * HashMap that implements Python dict.get(key, default) function.
+     * Default java.util .get(key) is then the same as .get(key, null);
+     */
+    static class CleverMap<K,V> extends HashMap<K,V> {
+        V get(K key, V defaultValue) {
+            if (containsKey(key))
+                return get(key);
+            else
+                return defaultValue;
+        }
+    }
+
+    public static class ExtraKeyDisplayMap extends CleverMap<String, String> {}
+
+
+
+    /*
+     * Multiple maps are available to quickly change
+     * the style of the keys.
+     */
+
+    public static class EXTRA_KEY_DISPLAY_MAPS {
+        /**
+         * Keys are displayed in a natural looking way, like "→" for "RIGHT"
+         */
+        public static final ExtraKeyDisplayMap CLASSIC_ARROWS_DISPLAY = new ExtraKeyDisplayMap() {{
+            // classic arrow keys (for ◀ ▶ ▲ ▼ @see arrowVariationDisplay)
+            put("LEFT", "←"); // U+2190 ← LEFTWARDS ARROW
+            put("RIGHT", "→"); // U+2192 → RIGHTWARDS ARROW
+            put("UP", "↑"); // U+2191 ↑ UPWARDS ARROW
+            put("DOWN", "↓"); // U+2193 ↓ DOWNWARDS ARROW
+        }};
+
+        public static final ExtraKeyDisplayMap WELL_KNOWN_CHARACTERS_DISPLAY = new ExtraKeyDisplayMap() {{
+            // well known characters // https://en.wikipedia.org/wiki/{Enter_key, Tab_key, Delete_key}
+            put("ENTER", "↲"); // U+21B2 ↲ DOWNWARDS ARROW WITH TIP LEFTWARDS
+            put("TAB", "↹"); // U+21B9 ↹ LEFTWARDS ARROW TO BAR OVER RIGHTWARDS ARROW TO BAR
+            put("BKSP", "⌫"); // U+232B ⌫ ERASE TO THE LEFT sometimes seen and easy to understand
+            put("DEL", "⌦"); // U+2326 ⌦ ERASE TO THE RIGHT not well known but easy to understand
+            put("DRAWER", "☰"); // U+2630 ☰ TRIGRAM FOR HEAVEN not well known but easy to understand
+            put("KEYBOARD", "⌨"); // U+2328 ⌨ KEYBOARD not well known but easy to understand
+            put("PASTE", "⎘"); // U+2398
+        }};
+
+        public static final ExtraKeyDisplayMap LESS_KNOWN_CHARACTERS_DISPLAY = new ExtraKeyDisplayMap() {{
+            // https://en.wikipedia.org/wiki/{Home_key, End_key, Page_Up_and_Page_Down_keys}
+            // home key can mean "goto the beginning of line" or "goto first page" depending on context, hence the diagonal
+            put("HOME", "⇱"); // from IEC 9995 // U+21F1 ⇱ NORTH WEST ARROW TO CORNER
+            put("END", "⇲"); // from IEC 9995 // ⇲ // U+21F2 ⇲ SOUTH EAST ARROW TO CORNER
+            put("PGUP", "⇑"); // no ISO character exists, U+21D1 ⇑ UPWARDS DOUBLE ARROW will do the trick
+            put("PGDN", "⇓"); // no ISO character exists, U+21D3 ⇓ DOWNWARDS DOUBLE ARROW will do the trick
+        }};
+
+        public static final ExtraKeyDisplayMap ARROW_TRIANGLE_VARIATION_DISPLAY = new ExtraKeyDisplayMap() {{
+            // alternative to classic arrow keys
+            put("LEFT", "◀"); // U+25C0 ◀ BLACK LEFT-POINTING TRIANGLE
+            put("RIGHT", "▶"); // U+25B6 ▶ BLACK RIGHT-POINTING TRIANGLE
+            put("UP", "▲"); // U+25B2 ▲ BLACK UP-POINTING TRIANGLE
+            put("DOWN", "▼"); // U+25BC ▼ BLACK DOWN-POINTING TRIANGLE
+        }};
+
+        public static final ExtraKeyDisplayMap NOT_KNOWN_ISO_CHARACTERS = new ExtraKeyDisplayMap() {{
+            // Control chars that are more clear as text // https://en.wikipedia.org/wiki/{Function_key, Alt_key, Control_key, Esc_key}
+            // put("FN", "FN"); // no ISO character exists
+            put("CTRL", "⎈"); // ISO character "U+2388 ⎈ HELM SYMBOL" is unknown to people and never printed on computers, however "U+25C7 ◇ WHITE DIAMOND" is a nice presentation, and "^" for terminal app and mac is often used
+            put("ALT", "⎇"); // ISO character "U+2387 ⎇ ALTERNATIVE KEY SYMBOL'" is unknown to people and only printed as the Option key "⌥" on Mac computer
+            put("ESC", "⎋"); // ISO character "U+238B ⎋ BROKEN CIRCLE WITH NORTHWEST ARROW" is unknown to people and not often printed on computers
+        }};
+
+        public static final ExtraKeyDisplayMap NICER_LOOKING_DISPLAY = new ExtraKeyDisplayMap() {{
+            // nicer looking for most cases
+            put("-", "―"); // U+2015 ― HORIZONTAL BAR
+        }};
+
+        /**
+         * Full Iso
+         */
+        public static final ExtraKeyDisplayMap FULL_ISO_CHAR_DISPLAY = new ExtraKeyDisplayMap() {{
+            putAll(CLASSIC_ARROWS_DISPLAY);
+            putAll(WELL_KNOWN_CHARACTERS_DISPLAY);
+            putAll(LESS_KNOWN_CHARACTERS_DISPLAY); // NEW
+            putAll(NICER_LOOKING_DISPLAY);
+            putAll(NOT_KNOWN_ISO_CHARACTERS); // NEW
+        }};
+
+        /**
+         * Only arrows
+         */
+        public static final ExtraKeyDisplayMap ARROWS_ONLY_CHAR_DISPLAY = new ExtraKeyDisplayMap() {{
+            putAll(CLASSIC_ARROWS_DISPLAY);
+            // putAll(wellKnownCharactersDisplay); // REMOVED
+            // putAll(lessKnownCharactersDisplay); // REMOVED
+            putAll(NICER_LOOKING_DISPLAY);
+        }};
+
+        /**
+         * Classic symbols and less known symbols
+         */
+        public static final ExtraKeyDisplayMap LOTS_OF_ARROWS_CHAR_DISPLAY = new ExtraKeyDisplayMap() {{
+            putAll(CLASSIC_ARROWS_DISPLAY);
+            putAll(WELL_KNOWN_CHARACTERS_DISPLAY);
+            putAll(LESS_KNOWN_CHARACTERS_DISPLAY); // NEW
+            putAll(NICER_LOOKING_DISPLAY);
+        }};
+
+        /**
+         * Some classic symbols everybody knows
+         */
+        public static final ExtraKeyDisplayMap DEFAULT_CHAR_DISPLAY = new ExtraKeyDisplayMap() {{
+            putAll(CLASSIC_ARROWS_DISPLAY);
+            putAll(WELL_KNOWN_CHARACTERS_DISPLAY);
+            putAll(NICER_LOOKING_DISPLAY);
+            // all other characters are displayed as themselves
+        }};
+
+    }
+
+
+
+    /**
+     * Aliases for the keys
+     */
+    public static final ExtraKeyDisplayMap CONTROL_CHARS_ALIASES = new ExtraKeyDisplayMap() {{
+        put("ESCAPE", "ESC");
+        put("CONTROL", "CTRL");
+        put("RETURN", "ENTER"); // Technically different keys, but most applications won't see the difference
+        put("FUNCTION", "FN");
+        // no alias for ALT
+
+        // Directions are sometimes written as first and last letter for brevety
+        put("LT", "LEFT");
+        put("RT", "RIGHT");
+        put("DN", "DOWN");
+        // put("UP", "UP"); well, "UP" is already two letters
+
+        put("PAGEUP", "PGUP");
+        put("PAGE_UP", "PGUP");
+        put("PAGE UP", "PGUP");
+        put("PAGE-UP", "PGUP");
+
+        // no alias for HOME
+        // no alias for END
+
+        put("PAGEDOWN", "PGDN");
+        put("PAGE_DOWN", "PGDN");
+        put("PAGE-DOWN", "PGDN");
+
+        put("DELETE", "DEL");
+        put("BACKSPACE", "BKSP");
+
+        // easier for writing in termux.properties
+        put("BACKSLASH", "\\");
+        put("QUOTE", "\"");
+        put("APOSTROPHE", "'");
+    }};
+
+}
diff --git a/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysInfo.java b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysInfo.java
new file mode 100644
index 0000000000..7bf47d7d40
--- /dev/null
+++ b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysInfo.java
@@ -0,0 +1,211 @@
+package com.termux.shared.terminal.io.extrakeys;
+
+import android.view.View;
+import android.widget.Button;
+
+import androidx.annotation.NonNull;
+
+import com.termux.shared.terminal.io.extrakeys.ExtraKeysConstants.EXTRA_KEY_DISPLAY_MAPS;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+/**
+ * A {@link Class} that defines the info needed by {@link ExtraKeysView} to display the extra key
+ * views.
+ *
+ * The {@code propertiesInfo} passed to the constructors of this class must be json array of arrays.
+ * Each array element of the json array will be considered a separate row of keys.
+ * Each key can either be simple string that defines the name of the key or a json dict that defines
+ * advance info for the key. The syntax can be `'KEY'` or `{key: 'KEY'}`.
+ * For example `HOME` or `{key: 'HOME', ...}.
+ *
+ * In advance json dict mode, the key can also be a sequence of space separated keys instead of one
+ * key. This can be done by replacing `key` key/value pair of the dict with a `macro` key/value pair.
+ * The syntax is `{macro: 'KEY COMBINATION'}`. For example {macro: 'HOME RIGHT', ...}.
+ *
+ * In advance json dict mode, you can define a nested json dict with the `popup` key which will be
+ * used as the popup key and will be triggered on swipe up. The syntax can be
+ * `{key: 'KEY', popup: 'POPUP_KEY'}` or `{key: 'KEY', popup: {macro: 'KEY COMBINATION', display: 'Key combo'}}`.
+ * For example `{key: 'HOME', popup: {KEY: 'END', ...}, ...}`.
+ *
+ * In advance json dict mode, the key can also have a custom display name that can be used as the
+ * text to display on the button by defining the `display` key. The syntax is `{display: 'DISPLAY'}`.
+ * For example {display: 'Custom name', ...}.
+ *
+ * Examples:
+ * {@code
+ * # Empty:
+ * []
+ *
+ * # Single row:
+ * [[ESC, TAB, CTRL, ALT, {key: '-', popup: '|'}, DOWN, UP]]
+ *
+ * # 2 row:
+ * [['ESC','/',{key: '-', popup: '|'},'HOME','UP','END','PGUP'],
+ * ['TAB','CTRL','ALT','LEFT','DOWN','RIGHT','PGDN']]
+ *
+ * # Advance:
+ * [[
+ *   {key: ESC, popup: {macro: "CTRL f d", display: "tmux exit"}},
+ *   {key: CTRL, popup: {macro: "CTRL f BKSP", display: "tmux ←"}},
+ *   {key: ALT, popup: {macro: "CTRL f TAB", display: "tmux →"}},
+ *   {key: TAB, popup: {macro: "ALT a", display: A-a}},
+ *   {key: LEFT, popup: HOME},
+ *   {key: DOWN, popup: PGDN},
+ *   {key: UP, popup: PGUP},
+ *   {key: RIGHT, popup: END},
+ *   {macro: "ALT j", display: A-j, popup: {macro: "ALT g", display: A-g}},
+ *   {key: KEYBOARD, popup: {macro: "CTRL d", display: exit}}
+ * ]]
+ *
+ * }
+ *
+ * Aliases are also allowed for the keys that you can pass as {@code extraKeyAliasMap}. Check
+ * {@link ExtraKeysConstants#CONTROL_CHARS_ALIASES}.
+ *
+ * Its up to the {@link ExtraKeysView.IExtraKeysView} client on how to handle individual key values
+ * of an {@link ExtraKeyButton}. They are sent as is via
+ * {@link ExtraKeysView.IExtraKeysView#onExtraKeyButtonClick(View, ExtraKeyButton, Button)}. The
+ * {@link com.termux.shared.terminal.io.TerminalExtraKeys} which is an implementation of the interface,
+ * checks if the key is one of {@link ExtraKeysConstants#PRIMARY_KEY_CODES_FOR_STRINGS} and generates
+ * a {@link android.view.KeyEvent} for it, and if its not, then converts the key to code points by
+ * calling {@link CharSequence#codePoints()} and passes them to the terminal as literal strings.
+ *
+ * Examples:
+ * {@code
+ * "ENTER" will trigger the ENTER keycode
+ * "LEFT" will trigger the LEFT keycode and be displayed as "←"
+ * "→" will input a "→" character
+ * "−" will input a "−" character
+ * "-_-" will input the string "-_-"
+ * }
+ *
+ * For more info, check https://wiki.termux.com/wiki/Touch_Keyboard.
+ */
+public class ExtraKeysInfo {
+
+    /**
+     * Matrix of buttons to be displayed in {@link ExtraKeysView}.
+     */
+    private final ExtraKeyButton[][] mButtons;
+
+    /**
+     * Initialize {@link ExtraKeysInfo}.
+     *
+     * @param propertiesInfo The {@link String} containing the info to create the {@link ExtraKeysInfo}.
+     *                       Check the class javadoc for details.
+     * @param style The style to pass to {@link #getCharDisplayMapForStyle(String)} to get the
+     *              {@link ExtraKeysConstants.ExtraKeyDisplayMap} that defines the display text
+     *              mapping for the keys if a custom value is not defined by
+     *              {@link ExtraKeyButton#KEY_DISPLAY_NAME} for a key.
+     * @param extraKeyAliasMap The {@link ExtraKeysConstants.ExtraKeyDisplayMap} that defines the
+     *                           aliases for the actual key names. You can create your own or
+     *                           optionally pass {@link ExtraKeysConstants#CONTROL_CHARS_ALIASES}.
+     */
+    public ExtraKeysInfo(@NonNull String propertiesInfo, String style,
+                         @NonNull ExtraKeysConstants.ExtraKeyDisplayMap extraKeyAliasMap) throws JSONException {
+        mButtons = initExtraKeysInfo(propertiesInfo, getCharDisplayMapForStyle(style), extraKeyAliasMap);
+    }
+
+    /**
+     * Initialize {@link ExtraKeysInfo}.
+     *
+     * @param propertiesInfo The {@link String} containing the info to create the {@link ExtraKeysInfo}.
+     *                       Check the class javadoc for details.
+     * @param extraKeyDisplayMap The {@link ExtraKeysConstants.ExtraKeyDisplayMap} that defines the
+     *                           display text mapping for the keys if a custom value is not defined
+     *                           by {@link ExtraKeyButton#KEY_DISPLAY_NAME} for a key. You can create
+     *                           your own or optionally pass one of the values defined in
+     *                           {@link #getCharDisplayMapForStyle(String)}.
+     * @param extraKeyAliasMap The {@link ExtraKeysConstants.ExtraKeyDisplayMap} that defines the
+     *                           aliases for the actual key names. You can create your own or
+     *                           optionally pass {@link ExtraKeysConstants#CONTROL_CHARS_ALIASES}.
+     */
+    public ExtraKeysInfo(@NonNull String propertiesInfo,
+                         @NonNull ExtraKeysConstants.ExtraKeyDisplayMap extraKeyDisplayMap,
+                         @NonNull ExtraKeysConstants.ExtraKeyDisplayMap extraKeyAliasMap) throws JSONException {
+        mButtons = initExtraKeysInfo(propertiesInfo, extraKeyDisplayMap, extraKeyAliasMap);
+    }
+
+    private ExtraKeyButton[][] initExtraKeysInfo(@NonNull String propertiesInfo,
+                                                 @NonNull ExtraKeysConstants.ExtraKeyDisplayMap extraKeyDisplayMap,
+                                                 @NonNull ExtraKeysConstants.ExtraKeyDisplayMap extraKeyAliasMap) throws JSONException {
+        // Convert String propertiesInfo to Array of Arrays
+        JSONArray arr = new JSONArray(propertiesInfo);
+        Object[][] matrix = new Object[arr.length()][];
+        for (int i = 0; i < arr.length(); i++) {
+            JSONArray line = arr.getJSONArray(i);
+            matrix[i] = new Object[line.length()];
+            for (int j = 0; j < line.length(); j++) {
+                matrix[i][j] = line.get(j);
+            }
+        }
+
+        // convert matrix to buttons
+        ExtraKeyButton[][] buttons = new ExtraKeyButton[matrix.length][];
+        for (int i = 0; i < matrix.length; i++) {
+            buttons[i] = new ExtraKeyButton[matrix[i].length];
+            for (int j = 0; j < matrix[i].length; j++) {
+                Object key = matrix[i][j];
+
+                JSONObject jobject = normalizeKeyConfig(key);
+
+                ExtraKeyButton button;
+
+                if (!jobject.has(ExtraKeyButton.KEY_POPUP)) {
+                    // no popup
+                    button = new ExtraKeyButton(jobject, extraKeyDisplayMap, extraKeyAliasMap);
+                } else {
+                    // a popup
+                    JSONObject popupJobject = normalizeKeyConfig(jobject.get(ExtraKeyButton.KEY_POPUP));
+                    ExtraKeyButton popup = new ExtraKeyButton(popupJobject, extraKeyDisplayMap, extraKeyAliasMap);
+                    button = new ExtraKeyButton(jobject, popup, extraKeyDisplayMap, extraKeyAliasMap);
+                }
+
+                buttons[i][j] = button;
+            }
+        }
+
+        return buttons;
+    }
+
+    /**
+     * Convert "value" -> {"key": "value"}. Required by
+     * {@link ExtraKeyButton#ExtraKeyButton(JSONObject, ExtraKeyButton, ExtraKeysConstants.ExtraKeyDisplayMap, ExtraKeysConstants.ExtraKeyDisplayMap)}.
+     */
+    private static JSONObject normalizeKeyConfig(Object key) throws JSONException {
+        JSONObject jobject;
+        if (key instanceof String) {
+            jobject = new JSONObject();
+            jobject.put(ExtraKeyButton.KEY_KEY_NAME, key);
+        } else if (key instanceof JSONObject) {
+            jobject = (JSONObject) key;
+        } else {
+            throw new JSONException("An key in the extra-key matrix must be a string or an object");
+        }
+        return jobject;
+    }
+
+    public ExtraKeyButton[][] getMatrix() {
+        return mButtons;
+    }
+
+    @NonNull
+    public static ExtraKeysConstants.ExtraKeyDisplayMap getCharDisplayMapForStyle(String style) {
+        switch (style) {
+            case "arrows-only":
+                return EXTRA_KEY_DISPLAY_MAPS.ARROWS_ONLY_CHAR_DISPLAY;
+            case "arrows-all":
+                return EXTRA_KEY_DISPLAY_MAPS.LOTS_OF_ARROWS_CHAR_DISPLAY;
+            case "all":
+                return EXTRA_KEY_DISPLAY_MAPS.FULL_ISO_CHAR_DISPLAY;
+            case "none":
+                return new ExtraKeysConstants.ExtraKeyDisplayMap();
+            default:
+                return EXTRA_KEY_DISPLAY_MAPS.DEFAULT_CHAR_DISPLAY;
+        }
+    }
+
+}
diff --git a/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysView.java b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysView.java
new file mode 100644
index 0000000000..2749787ff0
--- /dev/null
+++ b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/ExtraKeysView.java
@@ -0,0 +1,646 @@
+package com.termux.shared.terminal.io.extrakeys;
+
+import android.annotation.SuppressLint;
+import android.content.Context;
+import android.os.Build;
+import android.os.Handler;
+import android.os.Looper;
+import android.provider.Settings;
+import android.util.AttributeSet;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.ScheduledExecutorService;
+
+import java.util.Map;
+import java.util.HashMap;
+import java.util.stream.Collectors;
+
+import android.view.HapticFeedbackConstants;
+import android.view.LayoutInflater;
+import android.view.MotionEvent;
+import android.view.View;
+import android.view.ViewConfiguration;
+import android.view.ViewGroup;
+import android.widget.Button;
+import android.widget.GridLayout;
+import android.widget.PopupWindow;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+/**
+ * A {@link View} showing extra keys (such as Escape, Ctrl, Alt) not normally available on an Android soft
+ * keyboards.
+ *
+ * To use it, add following to a layout file and import it in your activity layout file or inflate
+ * it with a {@link androidx.viewpager.widget.ViewPager}.:
+ * {@code
+ * <?xml version="1.0" encoding="utf-8"?>
+ * <com.termux.shared.terminal.io.extrakeys.ExtraKeysView xmlns:android="http://schemas.android.com/apk/res/android"
+ *     android:id="@+id/extra_keys"
+ *     style="?android:attr/buttonBarStyle"
+ *     android:layout_width="match_parent"
+ *     android:layout_height="match_parent"
+ *     android:layout_alignParentBottom="true"
+ *     android:orientation="horizontal" />
+ * }
+ *
+ * Then in your activity, get its reference by a call to {@link android.app.Activity#findViewById(int)}
+ * or {@link LayoutInflater#inflate(int, ViewGroup)} if using {@link androidx.viewpager.widget.ViewPager}.
+ * Then call {@link #setExtraKeysViewClient(IExtraKeysView)} and pass it the implementation of
+ * {@link IExtraKeysView} so that you can receive callbacks. You can also override other values set
+ * in {@link ExtraKeysView#ExtraKeysView(Context, AttributeSet)} by calling the respective functions.
+ * If you extend {@link ExtraKeysView}, you can also set them in the constructor, but do call super().
+ *
+ * After this you will have to make a call to {@link ExtraKeysView#reload(ExtraKeysInfo) and pass
+ * it the {@link ExtraKeysInfo} to load and display the extra keys. Read its class javadocs for more
+ * info on how to create it.
+ *
+ * Termux app defines the view in res/layout/view_terminal_toolbar_extra_keys and
+ * inflates it in TerminalToolbarViewPager.instantiateItem() and sets the {@link ExtraKeysView} client
+ * and calls {@link ExtraKeysView#reload(ExtraKeysInfo).
+ * The {@link ExtraKeysInfo} is created by TermuxAppSharedProperties.setExtraKeys().
+ * Then its got and the view height is adjusted in TermuxActivity.setTerminalToolbarHeight().
+ * The client used is TermuxTerminalExtraKeys, which extends
+ * {@link com.termux.shared.terminal.io.TerminalExtraKeys} to handle Termux app specific logic and
+ * leave the rest to the super class.
+ */
+public final class ExtraKeysView extends GridLayout {
+
+    /** The client for the {@link ExtraKeysView}. */
+    public interface IExtraKeysView {
+
+        /**
+         * This is called by {@link ExtraKeysView} when a button is clicked. This is also called
+         * for {@link #mRepetitiveKeys} and {@link ExtraKeyButton} that have a popup set.
+         * However, this is not called for {@link #mSpecialButtons}, whose state can instead be read
+         * via a call to {@link #readSpecialButton(SpecialButton, boolean)}.
+         *
+         * @param view The view that was clicked.
+         * @param buttonInfo The {@link ExtraKeyButton} for the button that was clicked.
+         *                   The button may be a {@link ExtraKeyButton#KEY_MACRO} set which can be
+         *                   checked with a call to {@link ExtraKeyButton#isMacro()}.
+         * @param button The {@link Button} that was clicked.
+         */
+        void onExtraKeyButtonClick(View view, ExtraKeyButton buttonInfo, Button button);
+
+        /**
+         * This is called by {@link ExtraKeysView} when a button is clicked so that the client
+         * can perform any hepatic feedback. This is only called in the {@link Button.OnClickListener}
+         * and not for every repeat. Its also called for {@link #mSpecialButtons}.
+         *
+         * @param view The view that was clicked.
+         * @param buttonInfo The {@link ExtraKeyButton} for the button that was clicked.
+         * @param button The {@link Button} that was clicked.
+         * @return Return {@code true} if the client handled the feedback, otherwise {@code false}
+         * so that {@link ExtraKeysView#performExtraKeyButtonHapticFeedback(View, ExtraKeyButton, Button)}
+         * can handle it depending on system settings.
+         */
+        boolean performExtraKeyButtonHapticFeedback(View view, ExtraKeyButton buttonInfo, Button button);
+
+    }
+
+
+    /** Defines the default value for {@link #mButtonTextColor}. */
+    public static final int DEFAULT_BUTTON_TEXT_COLOR = 0xFFFFFFFF;
+    /** Defines the default value for {@link #mButtonActiveTextColor}. */
+    public static final int DEFAULT_BUTTON_ACTIVE_TEXT_COLOR = 0xFF80DEEA;
+    /** Defines the default value for {@link #mButtonBackgroundColor}. */
+    public static final int DEFAULT_BUTTON_BACKGROUND_COLOR = 0x00000000;
+    /** Defines the default value for {@link #mButtonActiveBackgroundColor}. */
+    public static final int DEFAULT_BUTTON_ACTIVE_BACKGROUND_COLOR = 0xFF7F7F7F;
+
+
+    /** Defines the minimum allowed duration in milliseconds for {@link #mLongPressTimeout}. */
+    public static final int MIN_LONG_PRESS_DURATION = 200;
+    /** Defines the maximum allowed duration in milliseconds for {@link #mLongPressTimeout}. */
+    public static final int MAX_LONG_PRESS_DURATION = 3000;
+    /** Defines the fallback duration in milliseconds for {@link #mLongPressTimeout}. */
+    public static final int FALLBACK_LONG_PRESS_DURATION = 400;
+
+    /** Defines the minimum allowed duration in milliseconds for {@link #mLongPressRepeatDelay}. */
+    public static final int MIN_LONG_PRESS__REPEAT_DELAY = 5;
+    /** Defines the maximum allowed duration in milliseconds for {@link #mLongPressRepeatDelay}. */
+    public static final int MAX_LONG_PRESS__REPEAT_DELAY = 2000;
+    /** Defines the default duration in milliseconds for {@link #mLongPressRepeatDelay}. */
+    public static final int DEFAULT_LONG_PRESS_REPEAT_DELAY = 80;
+
+
+
+    /** The implementation of the {@link IExtraKeysView} that acts as a client for the {@link ExtraKeysView}. */
+    private IExtraKeysView mExtraKeysViewClient;
+
+    /** The map for the {@link SpecialButton} and their {@link SpecialButtonState}. Defaults to
+     * the one returned by {@link #getDefaultSpecialButtons(ExtraKeysView)}. */
+    private Map<SpecialButton, SpecialButtonState> mSpecialButtons;
+
+    /** The keys for the {@link SpecialButton} added to {@link #mSpecialButtons}. This is automatically
+     * set when the call to {@link #setSpecialButtons(Map)} is made. */
+    private Set<String> mSpecialButtonsKeys;
+
+
+    /**
+     * The list of keys for which auto repeat of key should be triggered if its extra keys button
+     * is long pressed. This is done by calling {@link IExtraKeysView#onExtraKeyButtonClick(View, ExtraKeyButton, Button)}
+     * every {@link #mLongPressRepeatDelay} seconds after {@link #mLongPressTimeout} has passed.
+     * The default keys are defined by {@link ExtraKeysConstants#PRIMARY_REPETITIVE_KEYS}.
+     */
+    private List<String> mRepetitiveKeys;
+
+
+    /** The text color for the extra keys button. Defaults to {@link #DEFAULT_BUTTON_TEXT_COLOR}. */
+    private int mButtonTextColor;
+    /** The text color for the extra keys button when its active.
+     * Defaults to {@link #DEFAULT_BUTTON_ACTIVE_TEXT_COLOR}. */
+    private int mButtonActiveTextColor;
+    /** The background color for the extra keys button. Defaults to {@link #DEFAULT_BUTTON_BACKGROUND_COLOR}. */
+    private int mButtonBackgroundColor;
+    /** The background color for the extra keys button when its active. Defaults to
+     * {@link #DEFAULT_BUTTON_ACTIVE_BACKGROUND_COLOR}. */
+    private int mButtonActiveBackgroundColor;
+
+
+    /**
+     * Defines the duration in milliseconds before a press turns into a long press. The default
+     * duration used is the one returned by a call to {@link ViewConfiguration#getLongPressTimeout()}
+     * which will return the system defined duration which can be changed in accessibility settings.
+     * The duration must be in between {@link #MIN_LONG_PRESS_DURATION} and {@link #MAX_LONG_PRESS_DURATION},
+     * otherwise {@link #FALLBACK_LONG_PRESS_DURATION} is used.
+     */
+    private int mLongPressTimeout;
+
+    /**
+     * Defines the duration in milliseconds for the delay between trigger of each repeat of
+     * {@link #mRepetitiveKeys}. The default value is defined by {@link #DEFAULT_LONG_PRESS_REPEAT_DELAY}.
+     * The duration must be in between {@link #MIN_LONG_PRESS__REPEAT_DELAY} and
+     * {@link #MAX_LONG_PRESS__REPEAT_DELAY}, otherwise {@link #DEFAULT_LONG_PRESS_REPEAT_DELAY} is used.
+     */
+    private int mLongPressRepeatDelay;
+
+
+    /** The popup window shown if {@link ExtraKeyButton#getPopup()} returns a {@code non-null} value
+     * and a swipe up action is done on an extra key. */
+    private PopupWindow mPopupWindow;
+
+    private ScheduledExecutorService mScheduledExecutor;
+    private Handler mHandler;
+    private SpecialButtonsLongHoldRunnable mSpecialButtonsLongHoldRunnable;
+    private int mLongPressCount;
+
+
+    public ExtraKeysView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+
+        setRepetitiveKeys(ExtraKeysConstants.PRIMARY_REPETITIVE_KEYS);
+        setSpecialButtons(getDefaultSpecialButtons(this));
+        setButtonColors(DEFAULT_BUTTON_TEXT_COLOR, DEFAULT_BUTTON_ACTIVE_TEXT_COLOR,
+                    DEFAULT_BUTTON_BACKGROUND_COLOR, DEFAULT_BUTTON_ACTIVE_BACKGROUND_COLOR);
+        setLongPressTimeout(ViewConfiguration.getLongPressTimeout());
+        setLongPressRepeatDelay(DEFAULT_LONG_PRESS_REPEAT_DELAY);
+    }
+
+
+    /** Get {@link #mExtraKeysViewClient}. */
+    public IExtraKeysView getExtraKeysViewClient() {
+        return mExtraKeysViewClient;
+    }
+
+    /** Set {@link #mExtraKeysViewClient}. */
+    public void setExtraKeysViewClient(IExtraKeysView extraKeysViewClient) {
+        mExtraKeysViewClient = extraKeysViewClient;
+    }
+
+
+    /** Get {@link #mRepetitiveKeys}. */
+    public List<String> getRepetitiveKeys() {
+        if (mRepetitiveKeys == null) return null;
+        return mRepetitiveKeys.stream().map(String::new).collect(Collectors.toList());
+    }
+
+    /** Set {@link #mRepetitiveKeys}. Must not be {@code null}. */
+    public void setRepetitiveKeys(@NonNull List<String> repetitiveKeys) {
+        mRepetitiveKeys = repetitiveKeys;
+    }
+
+
+    /** Get {@link #mSpecialButtons}. */
+    public Map<SpecialButton, SpecialButtonState> getSpecialButtons() {
+        if (mSpecialButtons == null) return null;
+        return mSpecialButtons.entrySet().stream().collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+    }
+
+    /** Get {@link #mSpecialButtonsKeys}. */
+    public Set<String> getSpecialButtonsKeys() {
+        if (mSpecialButtonsKeys == null) return null;
+        return mSpecialButtonsKeys.stream().map(String::new).collect(Collectors.toSet());
+    }
+
+    /** Set {@link #mSpecialButtonsKeys}. Must not be {@code null}. */
+    public void setSpecialButtons(@NonNull Map<SpecialButton, SpecialButtonState> specialButtons) {
+        mSpecialButtons = specialButtons;
+        mSpecialButtonsKeys = this.mSpecialButtons.keySet().stream().map(SpecialButton::getKey).collect(Collectors.toSet());
+    }
+
+
+    /**
+     * Set the {@link ExtraKeysView} button colors.
+     *
+     * @param buttonTextColor The value for {@link #mButtonTextColor}.
+     * @param buttonActiveTextColor The value for {@link #mButtonActiveTextColor}.
+     * @param buttonBackgroundColor The value for {@link #mButtonBackgroundColor}.
+     * @param buttonActiveBackgroundColor The value for {@link #mButtonActiveBackgroundColor}.
+     */
+    public void setButtonColors(int buttonTextColor, int buttonActiveTextColor, int buttonBackgroundColor, int buttonActiveBackgroundColor) {
+        mButtonTextColor = buttonTextColor;
+        mButtonActiveTextColor = buttonActiveTextColor;
+        mButtonBackgroundColor = buttonBackgroundColor;
+        mButtonActiveBackgroundColor = buttonActiveBackgroundColor;
+    }
+
+
+    /** Get {@link #mButtonTextColor}. */
+    public int getButtonTextColor() {
+        return mButtonTextColor;
+    }
+
+    /** Set {@link #mButtonTextColor}. */
+    public void setButtonTextColor(int buttonTextColor) {
+        mButtonTextColor = buttonTextColor;
+    }
+
+
+    /** Get {@link #mButtonActiveTextColor}. */
+    public int getButtonActiveTextColor() {
+        return mButtonActiveTextColor;
+    }
+
+    /** Set {@link #mButtonActiveTextColor}. */
+    public void setButtonActiveTextColor(int buttonActiveTextColor) {
+        mButtonActiveTextColor = buttonActiveTextColor;
+    }
+
+
+    /** Get {@link #mButtonBackgroundColor}. */
+    public int getButtonBackgroundColor() {
+        return mButtonBackgroundColor;
+    }
+
+    /** Set {@link #mButtonBackgroundColor}. */
+    public void setButtonBackgroundColor(int buttonBackgroundColor) {
+        mButtonBackgroundColor = buttonBackgroundColor;
+    }
+
+
+    /** Get {@link #mButtonActiveBackgroundColor}. */
+    public int getButtonActiveBackgroundColor() {
+        return mButtonActiveBackgroundColor;
+    }
+
+    /** Set {@link #mButtonActiveBackgroundColor}. */
+    public void setButtonActiveBackgroundColor(int buttonActiveBackgroundColor) {
+        mButtonActiveBackgroundColor = buttonActiveBackgroundColor;
+    }
+
+
+    /** Get {@link #mLongPressTimeout}. */
+    public int getLongPressTimeout() {
+        return mLongPressTimeout;
+    }
+
+    /** Set {@link #mLongPressTimeout}. */
+    public void setLongPressTimeout(int longPressDuration) {
+        if (longPressDuration >= MIN_LONG_PRESS_DURATION && longPressDuration <= MAX_LONG_PRESS_DURATION) {
+            mLongPressTimeout = longPressDuration;
+        } else {
+                mLongPressTimeout = FALLBACK_LONG_PRESS_DURATION;
+        }
+    }
+
+    /** Get {@link #mLongPressRepeatDelay}. */
+    public int getLongPressRepeatDelay() {
+        return mLongPressRepeatDelay;
+    }
+
+    /** Set {@link #mLongPressRepeatDelay}. */
+    public void setLongPressRepeatDelay(int longPressRepeatDelay) {
+        if (mLongPressRepeatDelay >= MIN_LONG_PRESS__REPEAT_DELAY && mLongPressRepeatDelay <= MAX_LONG_PRESS__REPEAT_DELAY) {
+            mLongPressRepeatDelay = longPressRepeatDelay;
+        } else {
+            mLongPressRepeatDelay = DEFAULT_LONG_PRESS_REPEAT_DELAY;
+        }
+    }
+
+
+    /** Get the default map that can be used for {@link #mSpecialButtons}. */
+    @NonNull
+    public Map<SpecialButton, SpecialButtonState> getDefaultSpecialButtons(ExtraKeysView extraKeysView) {
+        return new HashMap<SpecialButton, SpecialButtonState>() {{
+            put(SpecialButton.CTRL, new SpecialButtonState(extraKeysView));
+            put(SpecialButton.ALT, new SpecialButtonState(extraKeysView));
+            put(SpecialButton.SHIFT, new SpecialButtonState(extraKeysView));
+            put(SpecialButton.FN, new SpecialButtonState(extraKeysView));
+        }};
+    }
+
+
+
+    /**
+     * Reload this instance of {@link ExtraKeysView} with the info passed in {@code extraKeysInfo}.
+     *
+     * @param extraKeysInfo The {@link ExtraKeysInfo} that defines the necessary info for the extra keys.
+     */
+    @SuppressLint("ClickableViewAccessibility")
+    public void reload(ExtraKeysInfo extraKeysInfo) {
+        if (extraKeysInfo == null)
+            return;
+
+        for(SpecialButtonState state : mSpecialButtons.values())
+            state.buttons = new ArrayList<>();
+
+        removeAllViews();
+
+        ExtraKeyButton[][] buttons = extraKeysInfo.getMatrix();
+
+        setRowCount(buttons.length);
+        setColumnCount(maximumLength(buttons));
+
+        for (int row = 0; row < buttons.length; row++) {
+            for (int col = 0; col < buttons[row].length; col++) {
+                final ExtraKeyButton buttonInfo = buttons[row][col];
+
+                Button button;
+                if (isSpecialButton(buttonInfo)) {
+                    button = createSpecialButton(buttonInfo.getKey(), true);
+                    if (button == null) return;
+                } else {
+                    button = new Button(getContext(), null, android.R.attr.buttonBarButtonStyle);
+                }
+
+                button.setText(buttonInfo.getDisplay());
+                button.setTextColor(mButtonTextColor);
+                button.setPadding(0, 0, 0, 0);
+
+                button.setOnClickListener(view -> {
+                    performExtraKeyButtonHapticFeedback(view, buttonInfo, button);
+                    onAnyExtraKeyButtonClick(view, buttonInfo, button);
+                });
+
+                button.setOnTouchListener((view, event) -> {
+                    switch (event.getAction()) {
+                        case MotionEvent.ACTION_DOWN:
+                            view.setBackgroundColor(mButtonActiveBackgroundColor);
+                            // Start long press scheduled executors which will be stopped in next MotionEvent
+                            startScheduledExecutors(view, buttonInfo, button);
+                            return true;
+
+                        case MotionEvent.ACTION_MOVE:
+                            if (buttonInfo.getPopup() != null) {
+                                // Show popup on swipe up
+                                if (mPopupWindow == null && event.getY() < 0) {
+                                    stopScheduledExecutors();
+                                    view.setBackgroundColor(mButtonBackgroundColor);
+                                    showPopup(view, buttonInfo.getPopup());
+                                }
+                                if (mPopupWindow != null && event.getY() > 0) {
+                                    view.setBackgroundColor(mButtonActiveBackgroundColor);
+                                    dismissPopup();
+                                }
+                            }
+                            return true;
+
+                        case MotionEvent.ACTION_CANCEL:
+                            view.setBackgroundColor(mButtonBackgroundColor);
+                            stopScheduledExecutors();
+                            return true;
+
+                        case MotionEvent.ACTION_UP:
+                            view.setBackgroundColor(mButtonBackgroundColor);
+                            stopScheduledExecutors();
+                            // If ACTION_UP up was not from a repetitive key or was with a key with a popup button
+                            if (mLongPressCount == 0 || mPopupWindow != null) {
+                                // Trigger popup button click if swipe up complete
+                                if (mPopupWindow != null) {
+                                    dismissPopup();
+                                    if (buttonInfo.getPopup() != null) {
+                                        onAnyExtraKeyButtonClick(view, buttonInfo.getPopup(), button);
+                                    }
+                                } else {
+                                    view.performClick();
+                                }
+                            }
+                            return true;
+
+                        default:
+                            return true;
+                    }
+                });
+
+                LayoutParams param = new GridLayout.LayoutParams();
+                param.width = 0;
+                param.height = 0;
+                param.setMargins(0, 0, 0, 0);
+                param.columnSpec = GridLayout.spec(col, GridLayout.FILL, 1.f);
+                param.rowSpec = GridLayout.spec(row, GridLayout.FILL, 1.f);
+                button.setLayoutParams(param);
+
+                addView(button);
+            }
+        }
+    }
+
+
+
+    private void onExtraKeyButtonClick(View view, ExtraKeyButton buttonInfo, Button button) {
+        if (mExtraKeysViewClient != null)
+            mExtraKeysViewClient.onExtraKeyButtonClick(view, buttonInfo, button);
+    }
+
+    private void performExtraKeyButtonHapticFeedback(View view, ExtraKeyButton buttonInfo, Button button) {
+        if (mExtraKeysViewClient != null) {
+            // If client handled the feedback, then just return
+            if (mExtraKeysViewClient.performExtraKeyButtonHapticFeedback(view, buttonInfo, button))
+                return;
+        }
+
+        if (Settings.System.getInt(getContext().getContentResolver(),
+            Settings.System.HAPTIC_FEEDBACK_ENABLED, 0) != 0) {
+
+            if (Build.VERSION.SDK_INT >= 28) {
+                button.performHapticFeedback(HapticFeedbackConstants.KEYBOARD_TAP);
+            } else {
+                // Perform haptic feedback only if no total silence mode enabled.
+                if (Settings.Global.getInt(getContext().getContentResolver(), "zen_mode", 0) != 2) {
+                    button.performHapticFeedback(HapticFeedbackConstants.KEYBOARD_TAP);
+                }
+            }
+        }
+    }
+
+
+
+    private void onAnyExtraKeyButtonClick(View view, @NonNull ExtraKeyButton buttonInfo, Button button) {
+        if (isSpecialButton(buttonInfo)) {
+            if (mLongPressCount > 0) return;
+            SpecialButtonState state = mSpecialButtons.get(SpecialButton.valueOf(buttonInfo.getKey()));
+            if (state == null) return;
+
+            // Toggle active state and disable lock state if new state is not active
+            state.setIsActive(!state.isActive);
+            if (!state.isActive)
+                state.setIsLocked(false);
+        } else {
+            onExtraKeyButtonClick(view, buttonInfo, button);
+        }
+    }
+
+
+    private void startScheduledExecutors(View view, ExtraKeyButton buttonInfo, Button button) {
+        stopScheduledExecutors();
+        mLongPressCount = 0;
+        if (mRepetitiveKeys.contains(buttonInfo.getKey())) {
+            // Auto repeat key if long pressed until ACTION_UP stops it by calling stopScheduledExecutors.
+            // Currently, only one (last) repeat key can run at a time. Old ones are stopped.
+            mScheduledExecutor = Executors.newSingleThreadScheduledExecutor();
+            mScheduledExecutor.scheduleWithFixedDelay(() -> {
+                mLongPressCount++;
+                onExtraKeyButtonClick(view, buttonInfo, button);
+            }, mLongPressTimeout, mLongPressRepeatDelay, TimeUnit.MILLISECONDS);
+        } else if (isSpecialButton(buttonInfo)) {
+            // Lock the key if long pressed by running mSpecialButtonsLongHoldRunnable after
+            // waiting for mLongPressTimeout milliseconds. If user does not long press, then the
+            // ACTION_UP triggered will cancel the runnable by calling stopScheduledExecutors before
+            // it has a chance to run.
+            SpecialButtonState state = mSpecialButtons.get(SpecialButton.valueOf(buttonInfo.getKey()));
+            if (state == null) return;
+            if (mHandler == null)
+                mHandler = new Handler(Looper.getMainLooper());
+            mSpecialButtonsLongHoldRunnable = new SpecialButtonsLongHoldRunnable(state);
+            mHandler.postDelayed(mSpecialButtonsLongHoldRunnable, mLongPressTimeout);
+        }
+    }
+
+    private void stopScheduledExecutors() {
+        if (mScheduledExecutor != null) {
+            mScheduledExecutor.shutdownNow();
+            mScheduledExecutor = null;
+        }
+
+        if (mSpecialButtonsLongHoldRunnable != null && mHandler != null) {
+            mHandler.removeCallbacks(mSpecialButtonsLongHoldRunnable);
+            mSpecialButtonsLongHoldRunnable = null;
+        }
+    }
+
+    private class SpecialButtonsLongHoldRunnable implements Runnable {
+        private final SpecialButtonState mState;
+
+        public SpecialButtonsLongHoldRunnable(SpecialButtonState state) {
+            mState = state;
+        }
+
+        public void run() {
+            // Toggle active and lock state
+            mState.setIsLocked(!mState.isActive);
+            mState.setIsActive(!mState.isActive);
+            mLongPressCount++;
+        }
+    }
+
+
+
+    void showPopup(View view, ExtraKeyButton extraButton) {
+        int width = view.getMeasuredWidth();
+        int height = view.getMeasuredHeight();
+        Button button;
+        if (isSpecialButton(extraButton)) {
+            button = createSpecialButton(extraButton.getKey(), false);
+            if (button == null) return;
+        } else {
+            button = new Button(getContext(), null, android.R.attr.buttonBarButtonStyle);
+            button.setTextColor(mButtonTextColor);
+        }
+        button.setText(extraButton.getDisplay());
+        button.setPadding(0, 0, 0, 0);
+        button.setMinHeight(0);
+        button.setMinWidth(0);
+        button.setMinimumWidth(0);
+        button.setMinimumHeight(0);
+        button.setWidth(width);
+        button.setHeight(height);
+        button.setBackgroundColor(mButtonActiveBackgroundColor);
+        mPopupWindow = new PopupWindow(this);
+        mPopupWindow.setWidth(LayoutParams.WRAP_CONTENT);
+        mPopupWindow.setHeight(LayoutParams.WRAP_CONTENT);
+        mPopupWindow.setContentView(button);
+        mPopupWindow.setOutsideTouchable(true);
+        mPopupWindow.setFocusable(false);
+        mPopupWindow.showAsDropDown(view, 0, -2 * height);
+    }
+
+    private void dismissPopup() {
+        mPopupWindow.setContentView(null);
+        mPopupWindow.dismiss();
+        mPopupWindow = null;
+    }
+
+
+
+    /** Check whether a {@link ExtraKeyButton} is a {@link SpecialButton}. */
+    public boolean isSpecialButton(ExtraKeyButton button) {
+        return mSpecialButtonsKeys.contains(button.getKey());
+    }
+
+    /**
+     * Read whether {@link SpecialButton} registered in {@link #mSpecialButtons} is active or not.
+     *
+     * @param specialButton The {@link SpecialButton} to read.
+     * @param autoSetInActive Set to {@code true} if {@link SpecialButtonState#isActive} should be
+     *                        set {@code false} if button is not locked.
+     * @return Returns {@code null} if button does not exist in {@link #mSpecialButtons}. If button
+     *         exists, then returns {@code true} if the button is created in {@link ExtraKeysView}
+     *         and is active, otherwise {@code false}.
+     */
+    @Nullable
+    public Boolean readSpecialButton(SpecialButton specialButton, boolean autoSetInActive) {
+        SpecialButtonState state = mSpecialButtons.get(specialButton);
+        if (state == null) return null;
+
+        if (!state.isCreated || !state.isActive)
+            return false;
+
+        // Disable active state only if not locked
+        if (autoSetInActive && !state.isLocked)
+            state.setIsActive(false);
+
+        return true;
+    }
+
+    private Button createSpecialButton(String buttonKey, boolean needUpdate) {
+        SpecialButtonState state = mSpecialButtons.get(SpecialButton.valueOf(buttonKey));
+        if (state == null) return null;
+        state.setIsCreated(true);
+        Button button = new Button(getContext(), null, android.R.attr.buttonBarButtonStyle);
+        button.setTextColor(state.isActive ? mButtonActiveTextColor : mButtonTextColor);
+        if (needUpdate) {
+            state.buttons.add(button);
+        }
+        return button;
+    }
+
+
+
+    /**
+     * General util function to compute the longest column length in a matrix.
+     */
+    static int maximumLength(Object[][] matrix) {
+        int m = 0;
+        for (Object[] row : matrix)
+            m = Math.max(m, row.length);
+        return m;
+    }
+
+}
diff --git a/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/SpecialButton.java b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/SpecialButton.java
new file mode 100644
index 0000000000..34dc258b99
--- /dev/null
+++ b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/SpecialButton.java
@@ -0,0 +1,52 @@
+package com.termux.shared.terminal.io.extrakeys;
+
+import androidx.annotation.NonNull;
+
+import java.util.HashMap;
+
+/** The {@link Class} that implements special buttons for {@link ExtraKeysView}. */
+public class SpecialButton {
+
+    private static final HashMap<String, SpecialButton> map = new HashMap<>();
+
+    public static final SpecialButton CTRL = new SpecialButton("CTRL");
+    public static final SpecialButton ALT = new SpecialButton("ALT");
+    public static final SpecialButton SHIFT = new SpecialButton("SHIFT");
+    public static final SpecialButton FN = new SpecialButton("FN");
+
+    /** The special button key. */
+    private final String key;
+
+    /**
+     * Initialize a {@link SpecialButton}.
+     *
+     * @param key The unique key name for the special button. The key is registered in {@link #map}
+     *            with which the {@link SpecialButton} can be retrieved via a call to
+     *            {@link #valueOf(String)}.
+     */
+    public SpecialButton(@NonNull final String key) {
+        this.key = key;
+        map.put(key, this);
+    }
+
+    /** Get {@link #key} for this {@link SpecialButton}. */
+    public String getKey() {
+        return key;
+    }
+
+    /**
+     * Get the {@link SpecialButton} for {@code key}.
+     *
+     * @param key The unique key name for the special button.
+     */
+    public static SpecialButton valueOf(String key) {
+        return map.get(key);
+    }
+
+    @NonNull
+    @Override
+    public String toString() {
+        return key;
+    }
+
+}
diff --git a/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/SpecialButtonState.java b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/SpecialButtonState.java
new file mode 100644
index 0000000000..0af0359a9e
--- /dev/null
+++ b/termux-shared/src/main/java/com/termux/shared/terminal/io/extrakeys/SpecialButtonState.java
@@ -0,0 +1,49 @@
+package com.termux.shared.terminal.io.extrakeys;
+
+import android.widget.Button;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/** The {@link Class} that maintains a state of a {@link SpecialButton} */
+public class SpecialButtonState {
+
+    /** If special button has been created for the {@link ExtraKeysView}. */
+    boolean isCreated = false;
+    /** If special button is active. */
+    boolean isActive = false;
+    /** If special button is locked due to long hold on it and should not be deactivated if its
+     * state is read. */
+    boolean isLocked = false;
+
+    List<Button> buttons = new ArrayList<>();
+
+    ExtraKeysView mExtraKeysView;
+
+    /**
+     * Initialize a {@link SpecialButtonState} to maintain state of a {@link SpecialButton}.
+     *
+     * @param extraKeysView The {@link ExtraKeysView} instance in which the {@link SpecialButton}
+     *                      is to be registered.
+     */
+    public SpecialButtonState(ExtraKeysView extraKeysView) {
+        mExtraKeysView = extraKeysView;
+    }
+
+    /** Set {@link #isCreated}. */
+    public void setIsCreated(boolean value) {
+        isCreated = value;
+    }
+
+    /** Set {@link #isActive}. */
+    public void setIsActive(boolean value) {
+        isActive = value;
+        buttons.forEach(button -> button.setTextColor(value ? mExtraKeysView.getButtonActiveTextColor() : mExtraKeysView.getButtonTextColor()));
+    }
+
+    /** Set {@link #isLocked}. */
+    public void setIsLocked(boolean value) {
+        isLocked = value;
+    }
+
+}