List & Array PropertyDrawers

Prowl.Editor/Drawers/PropertyDrawerAsset.cs

@@ -4,7 +4,6 @@
 using Prowl.Editor.ImGUI.Widgets;
 using Prowl.Icons;
 using Prowl.Runtime;
-using System.IO;
 
 namespace Prowl.Editor.PropertyDrawers;
 

Prowl.Editor/Drawers/PropertyDrawerOrderable.cs

@@ -0,0 +1,139 @@
+using Hexa.NET.ImGui;
+using Prowl.Editor.ImGUI.Widgets;
+
+namespace Prowl.Editor.PropertyDrawers;
+
+public abstract class PropertyDrawerOrderable<T> : PropertyDrawer<T> where T : class
+{
+    protected abstract int GetCount(T value);
+    protected abstract object GetElement(T value, int index);
+    protected abstract void SetElement(T value, int index, object element);
+    protected abstract void RemoveElement(ref T value, int index);
+    protected abstract void AddElement(ref T value);
+
+    protected override bool Draw(string label, ref T? value, float width)
+    {
+        bool changed = false;
+        if (ImGui.TreeNode(label))
+        {
+            ImGui.PushID(label);
+            int arrayID = ImGui.GetItemID();
+            ImGui.Indent();
+
+            // Get current y so we can draw a background rectangle
+            var startY = ImGui.GetCursorScreenPos().Y;
+            var startX = ImGui.GetCursorScreenPos().X - 3;
+            ImGui.Indent();
+
+            width -= 28 + 2;
+
+            for (int i = 0; i < GetCount(value); i++)
+            {
+                ImGui.PushID(i);
+                var element = GetElement(value, i);
+
+                // Draw the Drag icon
+                ImGui.Selectable("=", new System.Numerics.Vector2(28, 0));
+                if (ImGui.IsItemHovered())
+                {
+                    if (ImGui.IsMouseClicked(ImGuiMouseButton.Right))
+                    {
+                        // Show the context menu on right-click
+                        ImGui.OpenPopup("ContextMenu");
+                    }
+                    DragnDrop.Drag(arrayID.ToString(), i);
+                }
+
+                if (DragnDrop.Drop<int>(out var dropped, arrayID.ToString()))
+                {
+                    // Swap the elements
+                    var draggedElement = GetElement(value, dropped);
+                    SetElement(value, dropped, element);
+                    SetElement(value, i, draggedElement);
+                    changed = true;
+                }
+
+                ImGui.SameLine();
+                ImGui.Indent(28);
+
+                if (PropertyDrawer.Draw($"Element {i}", ref element, width))
+                {
+                    SetElement(value, i, element);
+                    changed = true;
+                }
+                ImGui.Unindent(28);
+
+                // Context menu for deletion
+                if (ImGui.BeginPopup("ContextMenu"))
+                {
+                    if (ImGui.MenuItem("Delete"))
+                    {
+                        RemoveElement(ref value, i);
+                        changed = true;
+                    }
+                    ImGui.EndPopup();
+                }
+
+                ImGui.PopID();
+            }
+
+            ImGui.Unindent();
+
+            // Move two pixels up so the button is aligned with the tree node
+            if (ImGui.Button("Add Element", new(-1, 0)))
+            {
+                AddElement(ref value);
+                changed = true;
+            }
+
+            // Draw a background rectangle
+            var endY = ImGui.GetCursorScreenPos().Y;
+            var style = ImGui.GetStyle();
+            var color = style.Colors[(int)ImGuiCol.FrameBg];
+            ImGui.GetWindowDrawList().AddLine(new System.Numerics.Vector2(startX, startY), new System.Numerics.Vector2(startX, endY), ImGui.ColorConvertFloat4ToU32(color), 2);
+            ImGui.GetWindowDrawList().AddLine(new System.Numerics.Vector2(startX, endY), new System.Numerics.Vector2(startX + 9999, endY), ImGui.ColorConvertFloat4ToU32(color), 2);
+
+            ImGui.Unindent();
+            ImGui.PopID();
+            ImGui.TreePop();
+            ImGui.Columns(1);
+        }
+        return changed;
+    }
+}
+
+public class PropertyDrawerArray : PropertyDrawerOrderable<Array>
+{
+    protected override int GetCount(Array value) => value.Length;
+    protected override object GetElement(Array value, int index) => value.GetValue(index);
+    protected override void SetElement(Array value, int index, object element) => value.SetValue(element, index);
+    protected override void RemoveElement(ref Array value, int index)
+    {
+        var elementType = value.GetType().GetElementType();
+        var newArray = Array.CreateInstance(elementType, value.Length - 1);
+        Array.Copy(value, 0, newArray, 0, index);
+        Array.Copy(value, index + 1, newArray, index, value.Length - index - 1);
+        value = newArray;
+    }
+    protected override void AddElement(ref Array value)
+    {
+        var elementType = value.GetType().GetElementType();
+        var newArray = Array.CreateInstance(elementType, value.Length + 1);
+        Array.Copy(value, newArray, value.Length);
+        value = newArray;
+    }
+}
+
+public class PropertyDrawerList : PropertyDrawerOrderable<System.Collections.IList>
+{
+    protected override int GetCount(System.Collections.IList value) => value.Count;
+    protected override object GetElement(System.Collections.IList value, int index) => value[index];
+    protected override void SetElement(System.Collections.IList value, int index, object element) => value[index] = element;
+    protected override void RemoveElement(ref System.Collections.IList value, int index) => value.RemoveAt(index);
+    protected override void AddElement(ref System.Collections.IList value)
+    {
+        var elementType = value.GetType().GetGenericArguments()[0];
+        var element = Activator.CreateInstance(elementType);
+        value.Add(element);
+    }
+}