Disableable ContextMenuButtonItems (#124253)

Fixes https://github.com/flutter/flutter/issues/124247

| Native | Flutter before | Flutter after |
| --- | --- | --- |
| <img width="248" alt="Screenshot 2023-04-05 at 9 26 16 AM" src="https://user-images.githubusercontent.com/389558/230177116-154999e8-eef3-441d-9fe9-7063839a6b99.png"> | <img width="240" alt="Screenshot 2023-04-05 at 11 18 01 AM" src="https://user-images.githubusercontent.com/389558/230177125-1680e851-223e-4956-b5b6-1a24e11dc22a.png"> | <img width="226" alt="Screenshot 2023-04-05 at 11 17 36 AM" src="https://user-images.githubusercontent.com/389558/230177123-bde82134-67e1-4ce2-8eec-719eeb779bf4.png"> |

Also, it's now possible for anyone to create disabled buttons like this by setting ContextMenuButtonItem.onPressed to `null`.

packages/flutter/lib/src/cupertino/desktop_text_selection_toolbar_button.dart

@@ -69,7 +69,7 @@ class CupertinoDesktopTextSelectionToolbarButton extends StatefulWidget {
        child = null;
 
   /// {@macro flutter.cupertino.CupertinoTextSelectionToolbarButton.onPressed}
-  final VoidCallback onPressed;
+  final VoidCallback? onPressed;
 
   /// {@macro flutter.cupertino.CupertinoTextSelectionToolbarButton.child}
   final Widget? child;

packages/flutter/lib/src/cupertino/spell_check_suggestions_toolbar.dart

@@ -66,7 +66,7 @@ class CupertinoSpellCheckSuggestionsToolbar extends StatelessWidget {
           CupertinoLocalizations.of(editableTextState.context);
       return <ContextMenuButtonItem>[
         ContextMenuButtonItem(
-          onPressed: () {},
+          onPressed: null,
           label: localizations.noSpellCheckReplacementsLabel,
         )
       ];

packages/flutter/lib/src/material/desktop_text_selection_toolbar_button.dart

@@ -51,7 +51,7 @@ class DesktopTextSelectionToolbarButton extends StatelessWidget {
        );
 
   /// {@macro flutter.material.TextSelectionToolbarTextButton.onPressed}
-  final VoidCallback onPressed;
+  final VoidCallback? onPressed;
 
   /// {@macro flutter.material.TextSelectionToolbarTextButton.child}
   final Widget child;

packages/flutter/lib/src/widgets/context_menu_button_item.dart

@@ -47,7 +47,7 @@ class ContextMenuButtonItem {
   });
 
   /// The callback to be called when the button is pressed.
-  final VoidCallback onPressed;
+  final VoidCallback? onPressed;
 
   /// The type of button this represents.
   final ContextMenuButtonType type;

packages/flutter/test/cupertino/desktop_text_selection_toolbar_button_test.dart

@@ -14,10 +14,10 @@ void main() {
       CupertinoApp(
         home: Center(
           child: CupertinoDesktopTextSelectionToolbarButton(
-            child: const Text('Tap me'),
             onPressed: () {
               pressed = true;
             },
+            child: const Text('Tap me'),
           ),
         ),
       ),
@@ -34,8 +34,8 @@ void main() {
       CupertinoApp(
         home: Center(
           child: CupertinoDesktopTextSelectionToolbarButton(
-            child: const Text('Tap me'),
             onPressed: () { },
+            child: const Text('Tap me'),
           ),
         ),
       ),
@@ -71,4 +71,21 @@ void main() {
     ));
     expect(opacity.opacity.value, 1.0);
   });
+
+  testWidgets('passing null to onPressed disables the button', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      const CupertinoApp(
+        home: Center(
+          child: CupertinoDesktopTextSelectionToolbarButton(
+            onPressed: null,
+            child: Text('Tap me'),
+          ),
+        ),
+      ),
+    );
+
+    expect(find.byType(CupertinoButton), findsOneWidget);
+    final CupertinoButton button = tester.widget(find.byType(CupertinoButton));
+    expect(button.enabled, isFalse);
+  });
 }

packages/flutter/test/cupertino/spell_check_suggestions_toolbar_test.dart

@@ -61,7 +61,7 @@ void main() {
     expect(labels, isNot(contains('yeller')));
   });
 
-  testWidgets('buildButtonItems builds a "No Replacements Found" button when no suggestions', (WidgetTester tester) async {
+  testWidgets('buildButtonItems builds a disabled "No Replacements Found" button when no suggestions', (WidgetTester tester) async {
     await tester.pumpWidget(
       CupertinoApp(
         home: _FakeEditableText(),
@@ -73,8 +73,9 @@ void main() {
         CupertinoSpellCheckSuggestionsToolbar.buildButtonItems(editableTextState);
 
     expect(buttonItems, isNotNull);
-    expect(buttonItems!.length, 1);
-    expect(buttonItems.first.label, 'No Replacements Found');
+    expect(buttonItems, hasLength(1));
+    expect(buttonItems!.first.label, 'No Replacements Found');
+    expect(buttonItems.first.onPressed, isNull);
   });
 }
 

packages/flutter/test/cupertino/text_selection_toolbar_button_test.dart

@@ -71,4 +71,20 @@ void main() {
     ));
     expect(opacity.opacity.value, 1.0);
   });
+
+  testWidgets('passing null to onPressed disables the button', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      const CupertinoApp(
+        home: Center(
+          child: CupertinoTextSelectionToolbarButton(
+            child: Text('Tap me'),
+          ),
+        ),
+      ),
+    );
+
+    expect(find.byType(CupertinoButton), findsOneWidget);
+    final CupertinoButton button = tester.widget(find.byType(CupertinoButton));
+    expect(button.enabled, isFalse);
+  });
 }

packages/flutter/test/material/desktop_text_selection_toolbar_button_test.dart

@@ -14,10 +14,10 @@ void main() {
       MaterialApp(
         home: Center(
           child: DesktopTextSelectionToolbarButton(
-            child: const Text('Tap me'),
             onPressed: () {
               pressed = true;
             },
+            child: const Text('Tap me'),
           ),
         ),
       ),
@@ -28,4 +28,21 @@ void main() {
     await tester.tap(find.byType(DesktopTextSelectionToolbarButton));
     expect(pressed, true);
   });
+
+  testWidgets('passing null to onPressed disables the button', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      const MaterialApp(
+        home: Center(
+          child: DesktopTextSelectionToolbarButton(
+            onPressed: null,
+            child: Text('Cannot tap me'),
+          ),
+        ),
+      ),
+    );
+
+    expect(find.byType(TextButton), findsOneWidget);
+    final TextButton button = tester.widget(find.byType(TextButton));
+    expect(button.enabled, isFalse);
+  });
 }

packages/flutter/test/widgets/editable_text_test.dart

@@ -2424,7 +2424,7 @@ void main() {
       final ContextMenuButtonItem cutButton = items!.first;
       expect(cutButton.type, ContextMenuButtonType.cut);
 
-      cutButton.onPressed();
+      cutButton.onPressed?.call();
       await tester.pump();
 
       expect(controller.text, isEmpty);
@@ -2492,7 +2492,7 @@ void main() {
       final ContextMenuButtonItem copyButton = items!.first;
       expect(copyButton.type, ContextMenuButtonType.copy);
 
-      copyButton.onPressed();
+      copyButton.onPressed?.call();
       await tester.pump();
 
       expect(controller.text, equals(text));
@@ -2560,7 +2560,7 @@ void main() {
       // Setting data which will be pasted into the clipboard.
       await Clipboard.setData(const ClipboardData(text: text));
 
-      pasteButton.onPressed();
+      pasteButton.onPressed?.call();
       await tester.pump();
 
       expect(controller.text, equals(text + text));
@@ -2619,7 +2619,7 @@ void main() {
       final ContextMenuButtonItem selectAllButton = items!.first;
       expect(selectAllButton.type, ContextMenuButtonType.selectAll);
 
-      selectAllButton.onPressed();
+      selectAllButton.onPressed?.call();
       await tester.pump();
 
       expect(controller.text, equals(text));
@@ -15169,6 +15169,68 @@ testWidgets('Floating cursor ending with selection', (WidgetTester tester) async
       expect(find.text('DELETE'), matcher);
     });
 
+    testWidgets('can show spell check suggestions toolbar when there are no spell check results on iOS', (WidgetTester tester) async {
+      tester.binding.platformDispatcher.nativeSpellCheckServiceDefinedTestValue =
+        true;
+      const TextEditingValue value = TextEditingValue(
+        text: 'tset test test',
+        selection: TextSelection(affinity: TextAffinity.upstream, baseOffset: 0, extentOffset: 4),
+      );
+      controller.value = value;
+      await tester.pumpWidget(
+        CupertinoApp(
+          home: EditableText(
+            backgroundCursorColor: Colors.grey,
+            controller: controller,
+            focusNode: focusNode,
+            style: textStyle,
+            cursorColor: cursorColor,
+            selectionControls: materialTextSelectionControls,
+            spellCheckConfiguration:
+              const SpellCheckConfiguration(
+                misspelledTextStyle: CupertinoTextField.cupertinoMisspelledTextStyle,
+                spellCheckSuggestionsToolbarBuilder: CupertinoTextField.defaultSpellCheckSuggestionsToolbarBuilder,
+              ),
+          ),
+        ),
+      );
+
+      final EditableTextState state =
+          tester.state<EditableTextState>(find.byType(EditableText));
+
+      // Can't show the toolbar when there's no focus.
+      expect(state.showSpellCheckSuggestionsToolbar(), false);
+      await tester.pumpAndSettle();
+      expect(find.byType(CupertinoTextSelectionToolbarButton), findsNothing);
+
+      // Can't show the toolbar when there are no spell check results.
+      expect(state.showSpellCheckSuggestionsToolbar(), false);
+      await tester.pumpAndSettle();
+      expect(find.byType(CupertinoTextSelectionToolbarButton), findsNothing);
+
+      // Shows 'No Replacements Found' when there are spell check results but no
+      // suggestions.
+      state.spellCheckResults = const SpellCheckResults('test tset test', <SuggestionSpan>[SuggestionSpan(TextRange(start: 0, end: 4), <String>[])]);
+      state.renderEditable.selectWordsInRange(
+        from: Offset.zero,
+        cause: SelectionChangedCause.tap,
+      );
+
+      await tester.pumpAndSettle();
+      // Toolbar will only show on non-web platforms.
+      expect(state.showSpellCheckSuggestionsToolbar(), isTrue);
+      await tester.pumpAndSettle();
+
+      expect(find.byType(CupertinoTextSelectionToolbarButton), findsOneWidget);
+      expect(find.byType(CupertinoButton), findsOneWidget);
+      expect(find.text('No Replacements Found'), findsOneWidget);
+      final CupertinoButton button = tester.widget(find.byType(CupertinoButton));
+      expect(button.enabled, isFalse);
+    },
+      variant: const TargetPlatformVariant(<TargetPlatform>{ TargetPlatform.iOS }),
+      skip: kIsWeb, // [intended]
+    );
+
     testWidgets('cupertino spell check suggestions toolbar buttons correctly change the composing region', (WidgetTester tester) async {
       tester.binding.platformDispatcher.nativeSpellCheckServiceDefinedTestValue =
         true;

packages/flutter/test/widgets/selectable_region_test.dart

@@ -1754,7 +1754,7 @@ void main() {
     expect(buttonItems[0].type, ContextMenuButtonType.copy);
 
     // Press `Copy` item
-    buttonItems[0].onPressed.call();
+    buttonItems[0].onPressed?.call();
 
     final SelectableRegionState regionState = tester.state<SelectableRegionState>(find.byType(SelectableRegion));
 
@@ -1808,7 +1808,7 @@ void main() {
     expect(buttonItems[1].type, ContextMenuButtonType.selectAll);
 
     // Press `Select All` item
-    buttonItems[1].onPressed.call();
+    buttonItems[1].onPressed?.call();
 
     final SelectableRegionState regionState = tester.state<SelectableRegionState>(find.byType(SelectableRegion));