Fix nuanced SuperIme issue where Flutter reports IME closure to us, but we weren't releasing it, which caused the keyboard to never be able to come back up after it closes.

Author: matthew-carroll

super_editor/example_chat/lib/floating_chat_editor_demo/floating_chat_editor_demo_configured.dart

@@ -69,7 +69,7 @@ class _FloatingChatEditorBuilderDemoState extends State<FloatingChatEditorBuilde
         pageBuilder: (context, pageGeometry) {
           return _ChatPage(
             appBar: _buildAppBar(),
-            scrollPadding: EdgeInsets.only(bottom: pageGeometry.bottomSafeArea),
+            scrollPadding: EdgeInsets.only(bottom: pageGeometry.bottomSafeArea ?? 0),
           );
         },
         editorSheet: _buildEditorSheet(),

super_editor/lib/src/default_editor/document_ime/document_ime_communication.dart

@@ -26,6 +26,7 @@ class DocumentImeInputClient extends TextInputConnectionDecorator with TextInput
     required this.textDeltasDocumentEditor,
     required this.imeConnection,
     required this.onPerformSelector,
+    required this.onImeConnectionClosed,
     this.floatingCursorController,
   }) : super(imeConnection.value) {
     // Note: we don't listen to document changes because we expect that any change during IME
@@ -65,6 +66,20 @@ class DocumentImeInputClient extends TextInputConnectionDecorator with TextInput
   /// For the list of selectors, see [MacOsSelectors].
   final void Function(String selectorName) onPerformSelector;
 
+  /// Callback invoked when Flutter's IME system tells us that our connection
+  /// was closed.
+  ///
+  /// The owner of this client should update any references to reflect that an IME
+  /// connection is no longer available. If the IME connection came from `SuperIme`
+  /// then the owner of this client should release the shared IME. Failure to do this
+  /// can lead to buggy keyboard behavior with the following order of events:
+  ///
+  ///   1. Open an IME connection, show the keyboard
+  ///   2. Something causes the IME connection to close, which also closes the keyboard
+  ///   3. **You don't release the connection**
+  ///   4. You try to open the keyboard (using the existing connection) but nothing happens.
+  final VoidCallback onImeConnectionClosed;
+
   // TODO: get floating cursor out of here. Use a multi-client IME decorator to split responsibilities
   late FloatingCursorController? floatingCursorController;
 

super_editor/lib/src/default_editor/document_ime/shared_ime.dart

@@ -95,7 +95,7 @@ class SuperIme with ChangeNotifier {
       return;
     }
 
-    if (false == _imeConnection?.attached) {
+    if (_imeConnection != null && _imeConnection!.attached == false) {
       // We have a connection, but its been detached, and we can't re-attach
       // without creating a new connection. Throw it away.
       //

super_editor/lib/src/default_editor/document_ime/supereditor_ime_interactor.dart

@@ -408,6 +408,7 @@ class SuperEditorImeInteractorState extends State<SuperEditorImeInteractor> impl
         onPerformAction: (action) => _imeClient.performAction(action),
       ),
       imeConnection: _ownedImeConnection,
+      onImeConnectionClosed: () => SuperIme.instance.releaseOwnership(_myImeId),
       onPerformSelector: _onPerformSelector,
     );
   }