Added time picker entry mode callback and tests (#87595)

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

@@ -1786,6 +1786,9 @@ class _HourMinuteTextFieldState extends State<_HourMinuteTextField> with Restora
   }
 }
 
+/// Signature for when the time picker entry mode is changed.
+typedef EntryModeChangeCallback = void Function(TimePickerEntryMode);
+
 /// A material design time picker designed to appear inside a popup dialog.
 ///
 /// Pass this widget to [showDialog]. The value returned by [showDialog] is the
@@ -1807,6 +1810,7 @@ class TimePickerDialog extends StatefulWidget {
     this.minuteLabelText,
     this.restorationId,
     this.initialEntryMode = TimePickerEntryMode.dial,
+    this.onEntryModeChanged,
   }) : assert(initialTime != null),
        super(key: key);
 
@@ -1852,6 +1856,9 @@ class TimePickerDialog extends StatefulWidget {
   ///    Flutter.
   final String? restorationId;
 
+  /// Callback called when the selected entry mode is changed.
+  final EntryModeChangeCallback? onEntryModeChanged;
+
   @override
   State<TimePickerDialog> createState() => _TimePickerDialogState();
 }
@@ -1947,6 +1954,8 @@ class _TimePickerDialogState extends State<TimePickerDialog> with RestorationMix
   final RestorableBoolN _autofocusMinute = RestorableBoolN(null);
   final RestorableBool _announcedInitialTime = RestorableBool(false);
 
+  late final VoidCallback _entryModeListener;
+
   @override
   void didChangeDependencies() {
     super.didChangeDependencies();
@@ -1955,6 +1964,13 @@ class _TimePickerDialogState extends State<TimePickerDialog> with RestorationMix
     _announceModeOnce();
   }
 
+  @override
+  void initState() {
+    super.initState();
+    _entryModeListener = () => widget.onEntryModeChanged?.call(_entryMode.value);
+    _entryMode.addListener(_entryModeListener);
+  }
+
   @override
   String? get restorationId => widget.restorationId;
 
@@ -2288,6 +2304,7 @@ class _TimePickerDialogState extends State<TimePickerDialog> with RestorationMix
   void dispose() {
     _vibrateTimer?.cancel();
     _vibrateTimer = null;
+    _entryMode.removeListener(_entryModeListener);
     super.dispose();
   }
 }
@@ -2380,6 +2397,7 @@ Future<TimeOfDay?> showTimePicker({
   String? hourLabelText,
   String? minuteLabelText,
   RouteSettings? routeSettings,
+  EntryModeChangeCallback? onEntryModeChanged,
 }) async {
   assert(context != null);
   assert(initialTime != null);
@@ -2396,6 +2414,7 @@ Future<TimeOfDay?> showTimePicker({
     errorInvalidText: errorInvalidText,
     hourLabelText: hourLabelText,
     minuteLabelText: minuteLabelText,
+    onEntryModeChanged: onEntryModeChanged,
   );
   return showDialog<TimeOfDay>(
     context: context,

packages/flutter/test/material/time_picker_test.dart

@@ -903,6 +903,34 @@ void _testsInput() {
     expect(find.byType(TextField), findsNothing);
   });
 
+  testWidgets('Switching to dial entry mode triggers entry callback', (WidgetTester tester) async {
+    bool triggeredCallback = false;
+
+    await mediaQueryBoilerplate(tester, true, entryMode: TimePickerEntryMode.input, onEntryModeChange: (TimePickerEntryMode mode) {
+      if (mode == TimePickerEntryMode.dial) {
+        triggeredCallback = true;
+      }
+    });
+
+    await tester.tap(find.byIcon(Icons.access_time));
+    await tester.pumpAndSettle();
+    expect(triggeredCallback, true);
+  });
+
+  testWidgets('Switching to input entry mode triggers entry callback', (WidgetTester tester) async {
+    bool triggeredCallback = false;
+
+    await mediaQueryBoilerplate(tester, true, entryMode: TimePickerEntryMode.dial, onEntryModeChange: (TimePickerEntryMode mode) {
+      if (mode == TimePickerEntryMode.input) {
+        triggeredCallback = true;
+      }
+    });
+
+    await tester.tap(find.byIcon(Icons.keyboard));
+    await tester.pumpAndSettle();
+    expect(triggeredCallback, true);
+  });
+
   testWidgets('Can double tap hours (when selected) to enter input mode', (WidgetTester tester) async {
     await mediaQueryBoilerplate(tester, false, entryMode: TimePickerEntryMode.dial);
     final Finder hourFinder = find.ancestor(
@@ -1163,6 +1191,7 @@ Future<void> mediaQueryBoilerplate(
   String? minuteLabelText,
   String? errorInvalidText,
   bool accessibleNavigation = false,
+  EntryModeChangeCallback? onEntryModeChange,
 }) async {
   await tester.pumpWidget(
     Localizations(
@@ -1192,7 +1221,8 @@ Future<void> mediaQueryBoilerplate(
                         helpText: helpText,
                         hourLabelText: hourLabelText,
                         minuteLabelText: minuteLabelText,
-                        errorInvalidText: errorInvalidText
+                        errorInvalidText: errorInvalidText,
+                        onEntryModeChanged: onEntryModeChange,
                       );
                     },
                     child: const Text('X'),