From 5e8ab2b3c848a58eb0933b73ee7f84d47025ec5c Mon Sep 17 00:00:00 2001
From: Amir Panahandeh <amirpanahandeh@yahoo.com>
Date: Mon, 25 Mar 2024 17:46:08 +0330
Subject: [PATCH] Hide collapsed selection handle when editor is read-only
 (#299)

* Hide collapsed selection handle when editor is read-only
---
 packages/fleather/lib/src/widgets/editor.dart | 53 ++++++++++++++++---
 .../fleather/test/widgets/editor_test.dart    | 15 ++++++
 2 files changed, 62 insertions(+), 6 deletions(-)

diff --git a/packages/fleather/lib/src/widgets/editor.dart b/packages/fleather/lib/src/widgets/editor.dart
index cfe84230..d82e5eed 100644
--- a/packages/fleather/lib/src/widgets/editor.dart
+++ b/packages/fleather/lib/src/widgets/editor.dart
@@ -308,6 +308,8 @@ class _FleatherEditorState extends State<FleatherEditor>
     implements EditorTextSelectionGestureDetectorBuilderDelegate {
   GlobalKey<EditorState>? _editorKey;
 
+  bool _showSelectionHandles = false;
+
   @override
   GlobalKey<EditorState> get editableTextKey => widget.editorKey ?? _editorKey!;
 
@@ -342,10 +344,42 @@ class _FleatherEditorState extends State<FleatherEditor>
         _FleatherEditorSelectionGestureDetectorBuilder(state: this);
   }
 
-  static const Set<TargetPlatform> _mobilePlatforms = {
-    TargetPlatform.iOS,
-    TargetPlatform.android
-  };
+  void _handleSelectionChanged(
+      TextSelection selection, SelectionChangedCause? cause) {
+    final bool willShowSelectionHandles = _shouldShowSelectionHandles(cause);
+    if (willShowSelectionHandles != _showSelectionHandles) {
+      setState(() {
+        _showSelectionHandles = willShowSelectionHandles;
+      });
+    }
+  }
+
+  bool _shouldShowSelectionHandles(SelectionChangedCause? cause) {
+    // When the editor is activated by something that doesn't trigger the
+    // selection overlay, we shouldn't show the handles either.
+    if (!_selectionGestureDetectorBuilder.shouldShowSelectionToolbar) {
+      return false;
+    }
+
+    if (cause == SelectionChangedCause.keyboard) {
+      return false;
+    }
+
+    if (widget.readOnly && widget.controller.selection.isCollapsed) {
+      return false;
+    }
+
+    if (cause == SelectionChangedCause.longPress ||
+        cause == SelectionChangedCause.scribble) {
+      return true;
+    }
+
+    if (widget.controller.document.toPlainText().length > 2) {
+      return true;
+    }
+
+    return false;
+  }
 
   @override
   Widget build(BuildContext context) {
@@ -360,7 +394,6 @@ class _FleatherEditorState extends State<FleatherEditor>
     Color selectionColor;
     Radius? cursorRadius;
 
-    final showSelectionHandles = _mobilePlatforms.contains(theme.platform);
     final keyboardAppearance = widget.keyboardAppearance ?? theme.brightness;
 
     switch (theme.platform) {
@@ -445,7 +478,8 @@ class _FleatherEditorState extends State<FleatherEditor>
         opacityAnimates: cursorOpacityAnimates,
       ),
       selectionColor: selectionColor,
-      showSelectionHandles: showSelectionHandles,
+      showSelectionHandles: _showSelectionHandles,
+      onSelectionChanged: _handleSelectionChanged,
       selectionControls: textSelectionControls,
     );
 
@@ -532,6 +566,7 @@ class RawEditor extends StatefulWidget {
     required this.clipboardManager,
     this.showSelectionHandles = false,
     this.selectionControls,
+    this.onSelectionChanged,
     this.contextMenuBuilder = defaultContextMenuBuilder,
     this.spellCheckConfiguration,
     this.embedBuilder = defaultFleatherEmbedBuilder,
@@ -600,6 +635,10 @@ class RawEditor extends StatefulWidget {
   ///  * [showCursor], which controls the visibility of the cursor..
   final bool showSelectionHandles;
 
+  /// Called when the user changes the selection of text (including the cursor
+  /// location).
+  final SelectionChangedCallback? onSelectionChanged;
+
   /// Whether to show cursor.
   ///
   /// The cursor refers to the blinking caret when the editor is focused.
@@ -1431,6 +1470,8 @@ class RawEditorState extends EditorState
         bringIntoView(selection.extent);
       }
     }
+
+    widget.onSelectionChanged?.call(selection, cause);
   }
 
   EditorTextSelectionOverlay _createSelectionOverlay() {
diff --git a/packages/fleather/test/widgets/editor_test.dart b/packages/fleather/test/widgets/editor_test.dart
index b13495cb..b89ebb59 100644
--- a/packages/fleather/test/widgets/editor_test.dart
+++ b/packages/fleather/test/widgets/editor_test.dart
@@ -56,6 +56,21 @@ void main() {
       expect(widget.readOnly, true);
     });
 
+    testWidgets('Selection handle is hidden when editor is read-only',
+        (tester) async {
+      final editor = EditorSandBox(
+          tester: tester,
+          document: ParchmentDocument.fromDelta(Delta()..insert('Text\n')));
+      await editor.pump();
+      await editor.disable();
+      await tester.tapAt(
+          tester.getTopLeft(find.byType(RawEditor)) + const Offset(15, 5));
+      await tester.pumpAndSettle();
+      final handle = tester.widget(editor.findSelectionHandles().first)
+          as SelectionHandleOverlay;
+      expect(handle.visibility?.value, false);
+    }, variant: TargetPlatformVariant.only(TargetPlatform.android));
+
     testWidgets('ability to paste upon long press on an empty document',
         (tester) async {
       // if Clipboard not initialize (status 'unknown'), an shrunken toolbar appears