Double double tap toggles instead of error (#33802)

Fix exception that was happening when double-double-tapping a TextField (or double long tapping).

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

@@ -744,8 +744,9 @@ class _TextFieldState extends State<TextField> with AutomaticKeepAliveClientMixi
         from: details.globalPosition,
         cause: SelectionChangedCause.forcePress,
       );
-      if (_shouldShowSelectionToolbar)
-        _editableTextKey.currentState.showToolbar();
+      if (_shouldShowSelectionToolbar) {
+        _editableTextKey.currentState.toggleToolbar();
+      }
     }
   }
 
@@ -812,15 +813,18 @@ class _TextFieldState extends State<TextField> with AutomaticKeepAliveClientMixi
   }
 
   void _handleSingleLongTapEnd(LongPressEndDetails details) {
-    if (_shouldShowSelectionToolbar)
-      _editableTextKey.currentState.showToolbar();
+    if (widget.selectionEnabled) {
+      if (_shouldShowSelectionToolbar)
+        _editableTextKey.currentState.toggleToolbar();
+    }
   }
 
   void _handleDoubleTapDown(TapDownDetails details) {
     if (widget.selectionEnabled) {
       _renderEditable.selectWord(cause: SelectionChangedCause.doubleTap);
-      if (_shouldShowSelectionToolbar)
-        _editableTextKey.currentState.showToolbar();
+      if (_shouldShowSelectionToolbar) {
+        _editableText.toggleToolbar();
+      }
     }
   }
 

packages/flutter/test/material/text_field_test.dart

@@ -5220,6 +5220,70 @@ void main() {
     },
   );
 
+  testWidgets(
+    'double double tap toggles selection menu',
+    (WidgetTester tester) async {
+      final TextEditingController controller = TextEditingController(
+        text: '',
+      );
+      await tester.pumpWidget(
+        MaterialApp(
+          home: Material(
+            child: Center(
+              child: TextField(
+                controller: controller,
+              ),
+            ),
+          ),
+        ),
+      );
+
+      // Double tap on the same location shows the selection menu.
+      await tester.tapAt(textOffsetToPosition(tester, 0));
+      await tester.pump(const Duration(milliseconds: 50));
+      await tester.tapAt(textOffsetToPosition(tester, 0));
+      await tester.pump();
+      expect(find.text('PASTE'), findsOneWidget);
+
+      // Double tap again hides the selection menu.
+      await tester.tapAt(textOffsetToPosition(tester, 0));
+      await tester.pump(const Duration(milliseconds: 50));
+      await tester.tapAt(textOffsetToPosition(tester, 0));
+      await tester.pump();
+      expect(find.text('PASTE'), findsNWidgets(0));
+    },
+  );
+
+  testWidgets(
+    'double long press toggles selection menu',
+    (WidgetTester tester) async {
+      final TextEditingController controller = TextEditingController(
+        text: '',
+      );
+      await tester.pumpWidget(
+        MaterialApp(
+          home: Material(
+            child: Center(
+              child: TextField(
+                controller: controller,
+              ),
+            ),
+          ),
+        ),
+      );
+
+      // Long press shows the selection menu.
+      await tester.longPressAt(textOffsetToPosition(tester, 0));
+      await tester.pump();
+      expect(find.text('PASTE'), findsOneWidget);
+
+      // Double tap again hides the selection menu.
+      await tester.longPressAt(textOffsetToPosition(tester, 0));
+      await tester.pump();
+      expect(find.text('PASTE'), findsNWidgets(0));
+    },
+  );
+
   testWidgets(
     'double tap hold selects word (iOS)',
     (WidgetTester tester) async {