chore: move members of magnifier feature into a separate files when possible (not final yet)

lib/src/editor/editor.dart

@@ -34,6 +34,8 @@ import 'widgets/delegate.dart';
 import 'widgets/float_cursor.dart';
 import 'widgets/text/text_selection.dart';
 
+part './magnifier/quill_editor_magnifier_ext.dart';
+
 /// Base interface for editable render objects.
 abstract class RenderAbstractEditor implements TextLayoutMetrics {
   TextSelection selectWordAtPosition(TextPosition position);

lib/src/editor/magnifier/quill_editor_magnifier_ext.dart

@@ -0,0 +1,22 @@
+part of '../editor.dart';
+
+extension QuillEditorSelectionGestureDetectorBuilderMagnifierExt
+    on _QuillEditorSelectionGestureDetectorBuilder {
+  void _showMagnifierIfSupportedByPlatform(Offset positionToShow) {
+    switch (defaultTargetPlatform) {
+      case TargetPlatform.android:
+      case TargetPlatform.iOS:
+        editor?.showMagnifier(positionToShow);
+      default:
+    }
+  }
+
+  void _hideMagnifierIfSupportedByPlatform() {
+    switch (defaultTargetPlatform) {
+      case TargetPlatform.android:
+      case TargetPlatform.iOS:
+        editor?.hideMagnifier();
+      default:
+    }
+  }
+}

lib/src/editor/magnifier/quill_magnifier_controller.dart

@@ -0,0 +1,14 @@
+import 'package:flutter/widgets.dart';
+import 'package:meta/meta.dart';
+
+// TODO: See the difference between Flutter MagnifierController and QuillMagnifierController
+//    and document it.
+@internal
+@experimental
+abstract class QuillMagnifierController {
+  void showMagnifier(Offset positionToShow);
+
+  void updateMagnifier(Offset positionToShow);
+
+  void hideMagnifier();
+}

lib/src/editor/magnifier/quill_raw_editor_state_magnifier_ext.dart

@@ -0,0 +1,27 @@
+part of '../raw_editor/raw_editor_state.dart';
+
+extension QuillRawEditorStateMagnifierExt on QuillRawEditorState {
+  void _hideMagnifier() {
+    if (_selectionOverlay == null) return;
+    _selectionOverlay?.hideMagnifier();
+  }
+
+  void _showMagnifier(ui.Offset positionToShow) {
+    if (_hasFocus == false) return;
+    if (_selectionOverlay == null) return;
+    final position = renderEditor.getPositionForOffset(positionToShow);
+    if (_selectionOverlay!.magnifierIsVisible) {
+      _selectionOverlay!
+          .updateMagnifier(position, positionToShow, renderEditor);
+    } else {
+      _selectionOverlay!.showMagnifier(position, positionToShow, renderEditor);
+    }
+  }
+
+  void _updateMagnifier(ui.Offset positionToShow) =>
+      showMagnifier(positionToShow);
+
+  TextMagnifierConfiguration get _magnifierConfiguration =>
+      widget.configurations.magnifierConfiguration ??
+      TextMagnifier.adaptiveMagnifierConfiguration;
+}

lib/src/editor/magnifier/text_selection_magnifier_ext.dart

@@ -0,0 +1,116 @@
+part of '../widgets/text/text_selection.dart';
+
+final MagnifierController _magnifierController = MagnifierController();
+
+/// Restore the selection context menu after the magnifier is dismissed.
+/// Fix: https://github.com/singerdmx/flutter-quill/issues/2046
+bool _restoreToolbar = false;
+
+extension EditorTextSelectionOverlayMagnifierExt on EditorTextSelectionOverlay {
+  // build magnifier info
+  MagnifierInfo _buildMagnifier(
+      {required RenderEditor renderEditable,
+      required Offset globalGesturePosition,
+      required TextPosition currentTextPosition}) {
+    final globalRenderEditableTopLeft =
+        renderEditable.localToGlobal(Offset.zero);
+    final localCaretRect =
+        renderEditable.getLocalRectForCaret(currentTextPosition);
+
+    final lineAtOffset = renderEditable.getLineAtOffset(currentTextPosition);
+    final positionAtEndOfLine = TextPosition(
+      offset: lineAtOffset.extentOffset,
+      affinity: TextAffinity.upstream,
+    );
+
+    // Default affinity is downstream.
+    final positionAtBeginningOfLine = TextPosition(
+      offset: lineAtOffset.baseOffset,
+    );
+
+    final lineBoundaries = Rect.fromPoints(
+      renderEditable.getLocalRectForCaret(positionAtBeginningOfLine).topCenter,
+      renderEditable.getLocalRectForCaret(positionAtEndOfLine).bottomCenter,
+    );
+
+    return MagnifierInfo(
+      fieldBounds: globalRenderEditableTopLeft & renderEditable.size,
+      globalGesturePosition: globalGesturePosition,
+      caretRect: localCaretRect.shift(globalRenderEditableTopLeft),
+      currentLineBoundaries: lineBoundaries.shift(globalRenderEditableTopLeft),
+    );
+  }
+
+  void _showMagnifier(MagnifierInfo initialMagnifierInfo) {
+    // Hide toolbar
+    if (toolbar != null) {
+      _restoreToolbar = true;
+      hideToolbar();
+    } else {
+      _restoreToolbar = false;
+    }
+
+    // Update magnifier Info
+    _magnifierInfo.value = initialMagnifierInfo;
+
+    final builtMagnifier = magnifierConfiguration.magnifierBuilder(
+      context,
+      _magnifierController,
+      _magnifierInfo,
+    );
+
+    if (builtMagnifier == null) return;
+
+    _magnifierController.show(
+      context: context,
+      below: magnifierConfiguration.shouldDisplayHandlesInMagnifier
+          ? null
+          : _handles?.elementAtOrNull(0),
+      builder: (_) => builtMagnifier,
+    );
+  }
+
+  void _updateMagnifier(MagnifierInfo magnifierInfo) {
+    if (_magnifierController.overlayEntry == null) {
+      return;
+    }
+    _magnifierInfo.value = magnifierInfo;
+  }
+
+  // TODO: Why we're having private and public methods for showMagnifier, and updateMagnifier?
+  //      Is this internal API that is for public use?
+  //      Once we know the reason, explain and document it.
+
+  void showMagnifier(
+      TextPosition position, Offset offset, RenderEditor editor) {
+    _showMagnifier(
+      _buildMagnifier(
+        currentTextPosition: position,
+        globalGesturePosition: offset,
+        renderEditable: editor,
+      ),
+    );
+  }
+
+  void updateMagnifier(
+      TextPosition position, Offset offset, RenderEditor editor) {
+    _updateMagnifier(
+      _buildMagnifier(
+        currentTextPosition: position,
+        globalGesturePosition: offset,
+        renderEditable: editor,
+      ),
+    );
+  }
+
+  void hideMagnifier() {
+    if (_magnifierController.overlayEntry == null) {
+      return;
+    }
+    _magnifierController.hide();
+    if (_restoreToolbar) {
+      _restoreToolbar = false;
+      showToolbar();
+    }
+  }
+}

lib/src/editor/raw_editor/raw_editor.dart

@@ -1,19 +1,9 @@
-import 'dart:ui' show Offset;
-
-import 'package:flutter/widgets.dart'
-    show
-        AnimationController,
-        BuildContext,
-        ScrollController,
-        State,
-        StatefulWidget,
-        TextSelectionDelegate,
-        Widget,
-        immutable;
+import 'package:flutter/widgets.dart';
 
 import '../../common/structs/offset_value.dart';
 import '../../controller/quill_controller.dart';
 import '../editor.dart';
+import '../magnifier/quill_magnifier_controller.dart';
 import '../widgets/text/text_selection.dart';
 import 'config/raw_editor_configurations.dart';
 import 'raw_editor_state.dart';
@@ -73,7 +63,7 @@ class QuillEditorGlyphHeights {
 /// Base interface for the editor state which defines contract used by
 /// various mixins.
 abstract class EditorState extends State<QuillRawEditor>
-    implements TextSelectionDelegate {
+    implements TextSelectionDelegate, QuillMagnifierController {
   ScrollController get scrollController;
 
   RenderEditor get renderEditor;
@@ -95,11 +85,5 @@ abstract class EditorState extends State<QuillRawEditor>
 
   void requestKeyboard();
 
-  void showMagnifier(Offset positionToShow);
-
-  void updateMagnifier(Offset positionToShow);
-
-  void hideMagnifier();
-
   void toggleToolbar([bool hideHandles = true]);
 }

lib/src/editor/raw_editor/raw_editor_state.dart

@@ -43,6 +43,8 @@ import 'raw_editor_state_text_input_client_mixin.dart';
 import 'raw_editor_text_boundaries.dart';
 import 'scribble_focusable.dart';
 
+part '../magnifier/quill_raw_editor_state_magnifier_ext.dart';
+
 class QuillRawEditorState extends EditorState
     with
         AutomaticKeepAliveClientMixin<QuillRawEditor>,
@@ -1114,8 +1116,7 @@ class QuillRawEditorState extends EditorState
           ? null
           : (context) =>
               widget.configurations.contextMenuBuilder!(context, this),
-      magnifierConfiguration: widget.configurations.magnifierConfiguration ??
-          TextMagnifier.adaptiveMagnifierConfiguration,
+      magnifierConfiguration: _magnifierConfiguration,
     );
   }
 
@@ -1505,26 +1506,13 @@ class QuillRawEditorState extends EditorState
   bool get shareEnabled => false;
 
   @override
-  void hideMagnifier() {
-    if (_selectionOverlay == null) return;
-    _selectionOverlay?.hideMagnifier();
-  }
+  void hideMagnifier() => _hideMagnifier();
 
   @override
-  void showMagnifier(ui.Offset positionToShow) {
-    if (_hasFocus == false) return;
-    if (_selectionOverlay == null) return;
-    final position = renderEditor.getPositionForOffset(positionToShow);
-    if (_selectionOverlay!.magnifierIsVisible) {
-      _selectionOverlay!
-          .updateMagnifier(position, positionToShow, renderEditor);
-    } else {
-      _selectionOverlay!.showMagnifier(position, positionToShow, renderEditor);
-    }
-  }
+  void showMagnifier(ui.Offset positionToShow) =>
+      _showMagnifier(positionToShow);
 
   @override
-  void updateMagnifier(ui.Offset positionToShow) {
-    showMagnifier(positionToShow);
-  }
+  void updateMagnifier(ui.Offset positionToShow) =>
+      _updateMagnifier(positionToShow);
 }