Add Reconnect button to embedded disconnect overlay and restore VM service connection after sleep/wake

packages/devtools_app/lib/src/framework/observer/disconnect_observer.dart

@@ -9,6 +9,7 @@ import 'package:devtools_app_shared/ui.dart';
 import 'package:devtools_app_shared/utils.dart';
 import 'package:flutter/material.dart';
 
+import '../../framework/framework_core.dart';
 import '../../service/connected_app/connection_info.dart';
 import '../../shared/analytics/analytics.dart' as ga;
 import '../../shared/analytics/constants.dart' as gac;
@@ -37,6 +38,14 @@ class DisconnectObserverState extends State<DisconnectObserver>
 
   late ConnectedState currentConnectionState;
 
+  /// Stores the last known VM service URI so we can attempt to reconnect
+  /// after the connection is lost (e.g. when the machine sleeps).
+  String? _lastVmServiceUri;
+
+  final _isReconnecting = ValueNotifier<bool>(false);
+
+  final _reconnectErrorText = ValueNotifier<String?>(null);
+
   @override
   void initState() {
     super.initState();
@@ -59,8 +68,14 @@ class DisconnectObserverState extends State<DisconnectObserver>
             !currentConnectionState.connected &&
             !currentConnectionState.userInitiatedConnectionState) {
           // We became disconnected by means other than a manual disconnect
-          // action, so show the overlay and ensure the 'uri' query paraemter
+          // action, so show the overlay and ensure the 'uri' query parameter
           // has been cleared.
+          //
+          // Store the VM service URI before clearing so we can attempt
+          // reconnection later (e.g. after machine sleep/wake).
+          _lastVmServiceUri =
+              widget.routerDelegate.currentConfiguration?.params.vmServiceUri ??
+              serviceConnection.serviceManager.serviceUri;
           unawaited(widget.routerDelegate.clearUriParameter());
           showDisconnectedOverlay();
         }
@@ -71,6 +86,8 @@ class DisconnectObserverState extends State<DisconnectObserver>
   @override
   void dispose() {
     hideDisconnectedOverlay();
+    _isReconnecting.dispose();
+    _reconnectErrorText.dispose();
     super.dispose();
   }
 
@@ -120,34 +137,130 @@ class DisconnectObserverState extends State<DisconnectObserver>
       builder: (context) => Material(
         child: Container(
           color: theme.colorScheme.surface,
-          child: Center(
-            child: Column(
-              children: [
-                const Spacer(),
-                Text('Disconnected', style: theme.textTheme.headlineMedium),
-                const SizedBox(height: defaultSpacing),
-                if (!isEmbedded())
-                  ConnectToNewAppButton(
-                    routerDelegate: widget.routerDelegate,
-                    onPressed: hideDisconnectedOverlay,
-                    gaScreen: gac.devToolsMain,
-                  )
-                else
-                  const Text('Run a new debug session to reconnect.'),
-                const Spacer(),
-                if (offlineDataController.offlineDataJson.isNotEmpty) ...[
-                  ElevatedButton(
-                    onPressed: _reviewHistory,
-                    child: const Text('Review recent data (offline)'),
+          child: ValueListenableBuilder<bool>(
+            valueListenable: _isReconnecting,
+            builder: (context, isReconnecting, _) =>
+                ValueListenableBuilder<String?>(
+                  valueListenable: _reconnectErrorText,
+                  builder: (context, reconnectErrorText, _) => Center(
+                    child: Column(
+                      children: [
+                        const Spacer(),
+                        Text(
+                          'Disconnected',
+                          style: theme.textTheme.headlineMedium,
+                        ),
+                        const SizedBox(height: defaultSpacing),
+                        if (isReconnecting)
+                          const CircularProgressIndicator()
+                        else if (!isEmbedded())
+                          Row(
+                            mainAxisAlignment: MainAxisAlignment.center,
+                            children: [
+                              ElevatedButton(
+                                onPressed: _attemptReconnect,
+                                child: const Text('Reconnect'),
+                              ),
+                              const SizedBox(width: defaultSpacing),
+                              ConnectToNewAppButton(
+                                routerDelegate: widget.routerDelegate,
+                                onPressed: hideDisconnectedOverlay,
+                                gaScreen: gac.devToolsMain,
+                              ),
+                            ],
+                          )
+                        else
+                          Column(
+                            mainAxisSize: MainAxisSize.min,
+                            children: [
+                              ElevatedButton(
+                                onPressed: _attemptReconnect,
+                                child: const Text('Reconnect'),
+                              ),
+                              const SizedBox(height: defaultSpacing),
+                              Text(
+                                'Or run a new debug session to connect to it.',
+                                style: theme.textTheme.bodyMedium,
+                              ),
+                            ],
+                          ),
+                        if (reconnectErrorText case final error?) ...[
+                          const SizedBox(height: denseSpacing),
+                          Text(
+                            error,
+                            style: theme.regularTextStyle.copyWith(
+                              color: theme.colorScheme.error,
+                            ),
+                            textAlign: TextAlign.center,
+                          ),
+                        ],
+                        const Spacer(),
+                        if (offlineDataController
+                            .offlineDataJson
+                            .isNotEmpty) ...[
+                          ElevatedButton(
+                            onPressed: _reviewHistory,
+                            child: const Text('Review recent data (offline)'),
+                          ),
+                          const Spacer(),
+                        ],
+                      ],
+                    ),
                   ),
-                  const Spacer(),
-                ],
-              ],
-            ),
+                ),
           ),
         ),
       ),
     );
     return currentDisconnectedOverlay!;
   }
+
+  Future<void> _attemptReconnect() async {
+    _isReconnecting.value = true;
+    _reconnectErrorText.value = null;
+
+    var reconnectionSuccess = false;
+
+    try {
+      await dtdManager.reconnect();
+
+      final uri = _lastVmServiceUri;
+      if (uri != null &&
+          !serviceConnection.serviceManager.connectedState.value.connected) {
+        // Call initVmService directly — do NOT use routerDelegate.navigate()
+        // because that goes through _replaceStack which calls manuallyDisconnect
+        // when clearing the URI, causing the disconnect observer to suppress
+        // the overlay (userInitiatedConnectionState = true).
+        reconnectionSuccess = await FrameworkCore.initVmService(
+          serviceUriAsString: uri,
+          logException: false,
+          errorReporter: (title, error) {
+            _reconnectErrorText.value = '$title, $error';
+          },
+        );
+      } else {
+        reconnectionSuccess =
+            serviceConnection.serviceManager.connectedState.value.connected;
+      }
+    } catch (e) {
+      _reconnectErrorText.value = e.toString();
+    } finally {
+      _isReconnecting.value = false;
+
+      if (reconnectionSuccess ||
+          serviceConnection.serviceManager.connectedState.value.connected) {
+        // Success — also update the router so the URI is reflected in the URL.
+        unawaited(
+          widget.routerDelegate.updateArgsIfChanged({
+            DevToolsQueryParams.vmServiceUriKey: _lastVmServiceUri,
+          }),
+        );
+        _reconnectErrorText.value = null;
+        hideDisconnectedOverlay();
+      } else {
+        // Failed (stale URI, VM dead, etc.) — restore the overlay with buttons.
+        showDisconnectedOverlay();
+      }
+    }
+  }
 }

packages/devtools_app/lib/src/standalone_ui/ide_shared/not_connected_overlay.dart

@@ -52,7 +52,7 @@ class _NotConnectedOverlayState extends State<NotConnectedOverlay> {
           if (showReconnectButton)
             ElevatedButton(
               onPressed: () => dtdManager.reconnect(),
-              child: const Text('Retry'),
+              child: const Text('Reconnect'),
             ),
         ],
       ),

packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md

@@ -19,7 +19,9 @@ TODO: Remove this section if there are not any updates.
 
 ## Inspector updates
 
-TODO: Remove this section if there are not any updates.
+- Added a "Reconnect" button to the disconnected overlay in embedded/IDE mode,
+  and fixed reconnection to restore the VM service connection after machine
+  sleep/wake (#9683).
 
 ## Performance updates
 

packages/devtools_app/test/framework/observer/disconnect_observer_test.dart

@@ -4,24 +4,31 @@
 
 import 'package:devtools_app/devtools_app.dart';
 import 'package:devtools_app/src/framework/observer/disconnect_observer.dart';
+import 'package:devtools_app/src/shared/primitives/query_parameters.dart';
 import 'package:devtools_app/src/shared/framework/framework_controller.dart';
+import 'package:devtools_app_shared/service.dart';
 import 'package:devtools_app_shared/shared.dart';
 import 'package:devtools_app_shared/ui.dart';
 import 'package:devtools_app_shared/utils.dart';
 import 'package:devtools_test/devtools_test.dart';
 import 'package:devtools_test/helpers.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
+import 'package:mockito/mockito.dart';
 
 import '../../test_infra/matchers/matchers.dart';
 
 void main() {
   group('DisconnectObserver', () {
     late FakeServiceConnectionManager fakeServiceConnectionManager;
+    late MockDTDManager mockDtdManager;
 
     setUp(() {
       fakeServiceConnectionManager = FakeServiceConnectionManager();
+      mockDtdManager = MockDTDManager();
+      when(mockDtdManager.reconnect()).thenAnswer((_) async {});
       setGlobal(ServiceConnectionManager, fakeServiceConnectionManager);
+      setGlobal(DTDManager, mockDtdManager);
       setGlobal(FrameworkController, FrameworkController());
       setGlobal(OfflineDataController, OfflineDataController());
       setGlobal(IdeTheme, IdeTheme());
@@ -30,6 +37,7 @@ void main() {
     Future<void> pumpDisconnectObserver(
       WidgetTester tester, {
       Widget child = const Placeholder(),
+      DevToolsQueryParams? queryParams,
     }) async {
       await tester.pumpWidget(
         wrap(
@@ -41,6 +49,7 @@ void main() {
               );
             },
           ),
+          queryParams: queryParams,
         ),
       );
       await tester.pumpAndSettle();
@@ -67,8 +76,14 @@ void main() {
         find.byType(ConnectToNewAppButton),
         showingOverlay && !isEmbedded() ? findsOneWidget : findsNothing,
       );
+      // The Reconnect button should be present in both embedded and
+      // non-embedded modes when the overlay is showing.
       expect(
-        find.text('Run a new debug session to reconnect.'),
+        find.text('Reconnect'),
+        showingOverlay ? findsOneWidget : findsNothing,
+      );
+      expect(
+        find.text('Or run a new debug session to connect to it.'),
         showingOverlay && isEmbedded() ? findsOneWidget : findsNothing,
       );
       expect(
@@ -134,6 +149,40 @@ void main() {
         await showOverlayAndVerifyContents(tester);
       });
 
+      testWidgets(
+        'reconnect button restores previous VM service URI on success',
+        (WidgetTester tester) async {
+          const previousVmServiceUri = 'http://127.0.0.1:8181/';
+          when(mockDtdManager.reconnect()).thenAnswer((_) async {
+            fakeServiceConnectionManager.serviceManager.setConnectedState(true);
+          });
+
+          await pumpDisconnectObserver(
+            tester,
+            queryParams: DevToolsQueryParams({
+              DevToolsQueryParams.vmServiceUriKey: previousVmServiceUri,
+            }),
+          );
+          verifyObserverState(tester, connected: true, showingOverlay: false);
+
+          fakeServiceConnectionManager.serviceManager.setConnectedState(false);
+          await tester.pumpAndSettle();
+          verifyObserverState(tester, connected: false, showingOverlay: true);
+
+          await tester.tap(find.text('Reconnect'));
+          await tester.pumpAndSettle();
+
+          verify(mockDtdManager.reconnect()).called(1);
+          verifyObserverState(tester, connected: true, showingOverlay: false);
+          final context = tester.element(find.byType(DisconnectObserver));
+          final routerDelegate = DevToolsRouterDelegate.of(context);
+          expect(
+            routerDelegate.currentConfiguration!.params.vmServiceUri,
+            previousVmServiceUri,
+          );
+        },
+      );
+
       // Regression test for https://github.com/flutter/devtools/issues/8050.
       testWidgets('hides widgets at lower z-index', (
         WidgetTester tester,