android: Receive and handle shares from other apps.

Enables handling and receiving shares from other apps, for any
type of content (text, images, and other files).

Uses the new root component, `SharingRoot` and the new native
module `SharingModule`. Introduces a new route for sharing -
`SharingScreen` allowing sharing content via PMs or to Streams.

`react-navigation` code Suggested-by: Chris Bobbe <[email protected]>

Closes  #M117.

android/app/src/main/AndroidManifest.xml

@@ -43,20 +43,16 @@
         </intent-filter>
       </activity>
 
-    <!-- Disabled while the feature is experimental.  See #117 and #4124.
       <activity
         android:name=".sharing.ReceiveShareActivity"
-        android:configChanges="keyboard|keyboardHidden|orientation|screenSize"
         android:label="@string/app_name"
-        android:launchMode="singleTask"
-        android:windowSoftInputMode="adjustResize">
+        android:launchMode="singleTask">
         <intent-filter>
             <action android:name="android.intent.action.SEND" />
             <category android:name="android.intent.category.DEFAULT" />
             <data android:mimeType="*/*" />
         </intent-filter>
       </activity>
-    -->
 
       <!-- When `react-native run-android` learns from the decoy `package`
            attribute in our comment above that the application ID is

src/boot/AppEventHandlers.js

@@ -15,6 +15,7 @@ import {
   NotificationListener,
   notificationOnAppActive,
 } from '../notification';
+import { ShareReceivedListener, handleInitialShare } from '../sharing';
 import { appOnline, appOrientation, initSafeAreaInsets } from '../actions';
 import PresenceHeartbeat from '../presence/PresenceHeartbeat';
 
@@ -98,6 +99,7 @@ class AppEventHandlers extends PureComponent<Props> {
   };
 
   notificationListener = new NotificationListener(this.props.dispatch);
+  shareListener = new ShareReceivedListener(this.props.dispatch);
 
   handleMemoryWarning = () => {
     // Release memory here
@@ -106,7 +108,7 @@ class AppEventHandlers extends PureComponent<Props> {
   componentDidMount() {
     const { dispatch } = this.props;
     handleInitialNotification(dispatch);
-
+    handleInitialShare(dispatch);
     this.netInfoDisconnectCallback = NetInfo.addEventListener(this.handleConnectivityChange);
     AppState.addEventListener('change', this.handleAppStateChange);
     AppState.addEventListener('memoryWarning', this.handleMemoryWarning);
@@ -116,6 +118,7 @@ class AppEventHandlers extends PureComponent<Props> {
     // $FlowFixMe: libdef wrongly says callback's parameter is optional
     Orientation.addOrientationListener(this.handleOrientationChange);
     this.notificationListener.start();
+    this.shareListener.start();
   }
 
   componentWillUnmount() {
@@ -128,6 +131,7 @@ class AppEventHandlers extends PureComponent<Props> {
     // $FlowFixMe: libdef wrongly says callback's parameter is optional
     Orientation.removeOrientationListener(this.handleOrientationChange);
     this.notificationListener.stop();
+    this.shareListener.stop();
   }
 
   render() {

src/nav/AppNavigator.js

@@ -31,6 +31,7 @@ import TopicListScreen from '../topics/TopicListScreen';
 import EmojiPickerScreen from '../emoji/EmojiPickerScreen';
 import LegalScreen from '../settings/LegalScreen';
 import UserStatusScreen from '../user-status/UserStatusScreen';
+import SharingScreen from '../sharing/SharingScreen';
 
 export default createStackNavigator(
   // $FlowFixMe react-navigation types :-/ -- see a36814e80
@@ -65,6 +66,7 @@ export default createStackNavigator(
     notifications: { screen: NotificationsScreen },
     legal: { screen: LegalScreen },
     'user-status': { screen: UserStatusScreen },
+    sharing: { screen: SharingScreen },
   },
   {
     initialRouteName: 'main',

src/nav/navActions.js

@@ -9,6 +9,7 @@ import type {
   Narrow,
   UserOrBot,
   ApiResponseServerSettings,
+  SharedData,
 } from '../types';
 import { getSameRoutesCount } from '../selectors';
 
@@ -103,3 +104,6 @@ export const navigateToLegal = (): NavigationAction => StackActions.push({ route
 
 export const navigateToUserStatus = (): NavigationAction =>
   StackActions.push({ routeName: 'user-status' });
+
+export const navigateToSharing = (sharedData: SharedData): NavigationAction =>
+  StackActions.push({ routeName: 'sharing', params: { sharedData } });

src/nav/navReducer.js

@@ -64,6 +64,11 @@ const rehydrate = (state, action) => {
     return getStateForRoute('loading');
   }
 
+  // Dont switch to main UI if sharing screen is on.
+  if (state.routes.find(route => route.routeName === 'sharing')) {
+    return state;
+  }
+
   // Great: we have an active, logged-in account, and server data for it.
   // Show the main UI.
   return getStateForRoute('main');

src/sharing/ChooseRecipientsScreen.js

@@ -0,0 +1,44 @@
+/* @flow strict-local */
+import React, { PureComponent } from 'react';
+import type { User, Dispatch } from '../types';
+import { connect } from '../react-redux';
+import { Screen } from '../common';
+import UserPickerCard from '../user-picker/UserPickerCard';
+
+type Props = $ReadOnly<{|
+  dispatch: Dispatch,
+  onComplete: (User[]) => void,
+|}>;
+
+type State = {|
+  filter: string,
+|};
+
+class ChooseRecipientsScreen extends PureComponent<Props, State> {
+  state = {
+    filter: '',
+  };
+
+  handleFilterChange = (filter: string) => this.setState({ filter });
+
+  handleComplete = (selected: Array<User>) => {
+    const { onComplete } = this.props;
+    onComplete(selected);
+  };
+
+  render() {
+    const { filter } = this.state;
+    return (
+      <Screen
+        search
+        scrollEnabled={false}
+        searchBarOnChange={this.handleFilterChange}
+        canGoBack={false}
+      >
+        <UserPickerCard filter={filter} onComplete={this.handleComplete} />
+      </Screen>
+    );
+  }
+}
+
+export default connect<{||}, _, _>()(ChooseRecipientsScreen);