From a777f3197d19ab1686d5933ba00e1280b37501a0 Mon Sep 17 00:00:00 2001
From: Elliott Brooks <21270878+elliette@users.noreply.github.com>
Date: Tue, 25 Mar 2025 10:49:57 -0700
Subject: [PATCH 1/6] Cherry-pick 51c6bfdf210ec7d65d4b732f83526ac13b06623c

---
 .../chart/controller/chart_connection.dart    |  4 +-
 .../screens/network/network_controller.dart   |  4 +-
 .../lib/src/shared/utils/utils.dart           | 36 +++++++--
 .../property_editor_controller.dart           | 77 +++++++++++++------
 .../test/shared/utils/utils_test.dart         | 67 ++++++++++++++--
 5 files changed, 149 insertions(+), 39 deletions(-)

diff --git a/packages/devtools_app/lib/src/screens/memory/panes/chart/controller/chart_connection.dart b/packages/devtools_app/lib/src/screens/memory/panes/chart/controller/chart_connection.dart
index 42b971e79ac..acfc21f15ba 100644
--- a/packages/devtools_app/lib/src/screens/memory/panes/chart/controller/chart_connection.dart
+++ b/packages/devtools_app/lib/src/screens/memory/panes/chart/controller/chart_connection.dart
@@ -36,7 +36,7 @@ class ChartVmConnection extends DisposableController
 
   bool initialized = false;
 
-  DebounceTimer? _polling;
+  PeriodicDebouncer? _polling;
 
   late final bool isDeviceAndroid;
 
@@ -79,7 +79,7 @@ class ChartVmConnection extends DisposableController
       ),
     );
 
-    _polling = DebounceTimer.periodic(chartUpdateDelay, ({
+    _polling = PeriodicDebouncer.run(chartUpdateDelay, ({
       DebounceCancelledCallback? cancelledCallback,
     }) async {
       if (!_isConnected) {
diff --git a/packages/devtools_app/lib/src/screens/network/network_controller.dart b/packages/devtools_app/lib/src/screens/network/network_controller.dart
index e84d45d28c5..2a29eafbdb3 100644
--- a/packages/devtools_app/lib/src/screens/network/network_controller.dart
+++ b/packages/devtools_app/lib/src/screens/network/network_controller.dart
@@ -160,7 +160,7 @@ class NetworkController extends DevToolsScreenController
   /// This timestamp is on the monotonic clock used by the timeline.
   int lastSocketDataRefreshMicros = 0;
 
-  DebounceTimer? _pollingTimer;
+  PeriodicDebouncer? _pollingTimer;
 
   @visibleForTesting
   bool get isPolling => _pollingTimer != null;
@@ -272,7 +272,7 @@ class NetworkController extends DevToolsScreenController
 
   void _updatePollingState(bool recording) {
     if (recording) {
-      _pollingTimer ??= DebounceTimer.periodic(
+      _pollingTimer ??= PeriodicDebouncer.run(
         // TODO(kenz): look into improving performance by caching more data.
         // Polling less frequently helps performance.
         _pollingDuration,
diff --git a/packages/devtools_app/lib/src/shared/utils/utils.dart b/packages/devtools_app/lib/src/shared/utils/utils.dart
index 5b96f475e35..e023b599d4c 100644
--- a/packages/devtools_app/lib/src/shared/utils/utils.dart
+++ b/packages/devtools_app/lib/src/shared/utils/utils.dart
@@ -185,17 +185,43 @@ extension IsKeyType on KeyEvent {
   bool get isKeyDownOrRepeat => this is KeyDownEvent || this is KeyRepeatEvent;
 }
 
+/// A helper class for [Timer] functionality, where the callbacks are debounced.
+class Debouncer extends Disposable {
+  Debouncer({required this.duration});
+
+  final Duration duration;
+  Timer? _activeTimer;
+
+  /// Invokes the [callback] once after the specified [duration] has elapsed.
+  ///
+  /// If multiple invokations are called while the timer is running, only the
+  /// last one will be called once no more invokations happen within the given
+  /// [duration].
+  void run(void Function() callback) {
+    if (disposed) return;
+    _activeTimer?.cancel();
+    _activeTimer = Timer(duration, callback);
+  }
+
+  @override
+  void dispose() {
+    _activeTimer?.cancel();
+    _activeTimer = null;
+    super.dispose();
+  }
+}
+
 typedef DebounceCancelledCallback = bool Function();
 
-/// A helper class for [Timer] functionality, where the callbacks are debounced.
-class DebounceTimer {
-  /// A periodic timer that ensures [callback] is only called at most once
-  /// per [duration].
+/// A periodic debouncer that calls the given [callback] at most once per
+/// [duration].
+class PeriodicDebouncer {
+  /// Start running the periodic debouncer.
   ///
   /// [callback] is triggered once immediately, and then every [duration] the
   /// timer checks to see if the previous [callback] call has finished running.
   /// If it has finished, then then next call to [callback] will begin.
-  DebounceTimer.periodic(
+  PeriodicDebouncer.run(
     Duration duration,
     Future<void> Function({DebounceCancelledCallback? cancelledCallback})
     callback,
diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart
index 3f2be326c8f..5f8a493a845 100644
--- a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart
@@ -9,6 +9,7 @@ import '../../../shared/analytics/analytics.dart' as ga;
 import '../../../shared/analytics/constants.dart' as gac;
 import '../../../shared/editor/api_classes.dart';
 import '../../../shared/editor/editor_client.dart';
+import '../../../shared/utils/utils.dart';
 
 typedef EditableWidgetData =
     ({List<EditableArgument> args, String? name, String? documentation});
@@ -22,7 +23,7 @@ typedef EditArgumentFunction =
 class PropertyEditorController extends DisposableController
     with AutoDisposeControllerMixin {
   PropertyEditorController(this.editorClient) {
-    _init();
+    init();
   }
 
   final EditorClient editorClient;
@@ -36,7 +37,15 @@ class PropertyEditorController extends DisposableController
       _editableWidgetData;
   final _editableWidgetData = ValueNotifier<EditableWidgetData?>(null);
 
-  void _init() {
+  late final Debouncer _editableArgsDebouncer;
+
+  static const _editableArgsDebounceDuration = Duration(milliseconds: 600);
+
+  @override
+  void init() {
+    super.init();
+    _editableArgsDebouncer = Debouncer(duration: _editableArgsDebounceDuration);
+
     autoDisposeStreamSubscription(
       editorClient.activeLocationChangedStream.listen((event) async {
         final textDocument = event.textDocument;
@@ -45,34 +54,33 @@ class PropertyEditorController extends DisposableController
         if (textDocument == null) {
           return;
         }
-        // Don't do anything if the event corresponds to the current position.
-        if (textDocument == _currentDocument &&
+        // Don't do anything if the event corresponds to the current position
+        // and document version.
+        //
+        // Note: This is only checked if the document version is not null. For
+        // IntelliJ, the document verison is always null, so identical events
+        // indicating a valid change are possible.
+        if (textDocument.version != null &&
+            textDocument == _currentDocument &&
             cursorPosition == _currentCursorPosition) {
           return;
         }
-        _currentDocument = textDocument;
-        _currentCursorPosition = cursorPosition;
-        // Get the editable arguments for the current position.
-        final result = await editorClient.getEditableArguments(
-          textDocument: textDocument,
-          position: cursorPosition,
-        );
-        final args = result?.args ?? <EditableArgument>[];
-        final name = result?.name;
-        _editableWidgetData.value = (
-          args: args,
-          name: name,
-          documentation: result?.documentation,
-        );
-        // Register impression.
-        ga.impression(
-          gaId,
-          gac.PropertyEditorSidebar.widgetPropertiesUpdate(name: name),
+        _editableArgsDebouncer.run(
+          () => _updateWithEditableArgs(
+            textDocument: textDocument,
+            cursorPosition: cursorPosition,
+          ),
         );
       }),
     );
   }
 
+  @override
+  void dispose() {
+    _editableArgsDebouncer.dispose();
+    super.dispose();
+  }
+
   Future<EditArgumentResponse?> editArgument<T>({
     required String name,
     required T value,
@@ -88,6 +96,31 @@ class PropertyEditorController extends DisposableController
     );
   }
 
+  Future<void> _updateWithEditableArgs({
+    required TextDocument textDocument,
+    required CursorPosition cursorPosition,
+  }) async {
+    _currentDocument = textDocument;
+    _currentCursorPosition = cursorPosition;
+    // Get the editable arguments for the current position.
+    final result = await editorClient.getEditableArguments(
+      textDocument: textDocument,
+      position: cursorPosition,
+    );
+    final args = result?.args ?? <EditableArgument>[];
+    final name = result?.name;
+    _editableWidgetData.value = (
+      args: args,
+      name: name,
+      documentation: result?.documentation,
+    );
+    // Register impression.
+    ga.impression(
+      gaId,
+      gac.PropertyEditorSidebar.widgetPropertiesUpdate(name: name),
+    );
+  }
+
   @visibleForTesting
   void initForTestsOnly({
     EditableArgumentsResult? editableArgsResult,
diff --git a/packages/devtools_app/test/shared/utils/utils_test.dart b/packages/devtools_app/test/shared/utils/utils_test.dart
index 9fa072201b2..b9cbdf7c9ec 100644
--- a/packages/devtools_app/test/shared/utils/utils_test.dart
+++ b/packages/devtools_app/test/shared/utils/utils_test.dart
@@ -12,11 +12,11 @@ import 'package:fake_async/fake_async.dart';
 import 'package:flutter_test/flutter_test.dart';
 
 void main() {
-  group('DebounceTimer', () {
+  group('PeriodicDebouncer', () {
     test('the callback happens immediately', () {
       fakeAsync((async) {
         int callbackCounter = 0;
-        DebounceTimer.periodic(const Duration(seconds: 1), ({
+        PeriodicDebouncer.run(const Duration(seconds: 1), ({
           DebounceCancelledCallback? cancelledCallback,
         }) async {
           callbackCounter++;
@@ -30,7 +30,7 @@ void main() {
     test('only triggers another callback after the first is done', () {
       fakeAsync((async) {
         int callbackCounter = 0;
-        DebounceTimer.periodic(const Duration(milliseconds: 500), ({
+        PeriodicDebouncer.run(const Duration(milliseconds: 500), ({
           DebounceCancelledCallback? cancelledCallback,
         }) async {
           callbackCounter++;
@@ -44,7 +44,7 @@ void main() {
     test('calls the callback at the beginning and then once per period', () {
       fakeAsync((async) {
         int callbackCounter = 0;
-        DebounceTimer.periodic(const Duration(seconds: 1), ({
+        PeriodicDebouncer.run(const Duration(seconds: 1), ({
           DebounceCancelledCallback? cancelledCallback,
         }) async {
           callbackCounter++;
@@ -60,7 +60,7 @@ void main() {
       () {
         fakeAsync((async) {
           int callbackCounter = 0;
-          final timer = DebounceTimer.periodic(const Duration(seconds: 1), ({
+          final timer = PeriodicDebouncer.run(const Duration(seconds: 1), ({
             DebounceCancelledCallback? cancelledCallback,
           }) async {
             callbackCounter++;
@@ -82,7 +82,7 @@ void main() {
       () {
         fakeAsync((async) {
           int callbackCounter = 0;
-          final timer = DebounceTimer.periodic(const Duration(seconds: 1), ({
+          final timer = PeriodicDebouncer.run(const Duration(seconds: 1), ({
             DebounceCancelledCallback? cancelledCallback,
           }) async {
             callbackCounter++;
@@ -102,7 +102,7 @@ void main() {
     test('cancels the callback when cancelled during the first callback', () {
       fakeAsync((async) {
         int callbackCounter = 0;
-        final timer = DebounceTimer.periodic(const Duration(seconds: 1), ({
+        final timer = PeriodicDebouncer.run(const Duration(seconds: 1), ({
           DebounceCancelledCallback? cancelledCallback,
         }) async {
           callbackCounter++;
@@ -123,7 +123,7 @@ void main() {
     test('cancels the callback when cancelled during the Nth callback', () {
       fakeAsync((async) {
         int callbackCounter = 0;
-        final timer = DebounceTimer.periodic(const Duration(seconds: 1), ({
+        final timer = PeriodicDebouncer.run(const Duration(seconds: 1), ({
           DebounceCancelledCallback? cancelledCallback,
         }) async {
           callbackCounter++;
@@ -142,6 +142,57 @@ void main() {
     });
   });
 
+  group('Debouncer', () {
+    late Debouncer debouncer;
+    late int callbackCount;
+
+    setUp(() {
+      callbackCount = 0;
+      debouncer = Debouncer(duration: const Duration(milliseconds: 100));
+    });
+
+    tearDown(() {
+      debouncer.dispose();
+    });
+
+    test('calls callback after duration', () async {
+      debouncer.run(() => callbackCount++);
+      expect(callbackCount, 0);
+      await Future.delayed(const Duration(milliseconds: 150));
+      expect(callbackCount, 1);
+    });
+
+    test('debounces multiple calls', () async {
+      debouncer.run(() => callbackCount++);
+      debouncer.run(() => callbackCount++);
+      debouncer.run(() => callbackCount++);
+      expect(callbackCount, 0);
+      await Future.delayed(const Duration(milliseconds: 150));
+      expect(callbackCount, 1);
+    });
+
+    test('calls callback after multiple calls with delay', () async {
+      debouncer.run(() => callbackCount++);
+      await Future.delayed(const Duration(milliseconds: 50));
+      debouncer.run(() => callbackCount++);
+      await Future.delayed(const Duration(milliseconds: 50));
+      debouncer.run(() => callbackCount++);
+      expect(callbackCount, 0);
+      await Future.delayed(const Duration(milliseconds: 150));
+      expect(callbackCount, 1);
+    });
+
+    test('dispose cancels timer', () async {
+      debouncer.run(() => callbackCount++);
+      debouncer.dispose();
+      await Future.delayed(const Duration(milliseconds: 150));
+      expect(callbackCount, 0);
+      debouncer.run(() => callbackCount++);
+      await Future.delayed(const Duration(milliseconds: 150));
+      expect(callbackCount, 0);
+    });
+  });
+
   group('InterruptableChunkWorker', () {
     late InterruptableChunkWorker worker;
     late List<int> indexes;

From 678ad9cc75b0e0ab41ebefad94370eb11e23204f Mon Sep 17 00:00:00 2001
From: Elliott Brooks <21270878+elliette@users.noreply.github.com>
Date: Thu, 20 Mar 2025 09:59:01 -0700
Subject: [PATCH 2/6] [Property Editor] Show reconnection overlay when
 disconnection detected (#9043)

---
 .../timeline_events/timeline_events_view.dart | 38 +++-------
 .../lib/src/shared/editor/editor_client.dart  | 21 ++++++
 .../lib/src/shared/ui/common_widgets.dart     | 55 ++++++++++++++
 .../property_editor_controller.dart           | 27 +++++++
 .../property_editor_panel.dart                | 49 ++++++++-----
 .../property_editor/property_editor_view.dart | 10 ++-
 .../property_editor/reconnecting_overlay.dart | 71 +++++++++++++++++++
 .../property_editor/utils/_utils_desktop.dart |  4 ++
 .../property_editor/utils/_utils_web.dart     |  4 ++
 .../property_editor/utils/utils.dart          |  7 ++
 10 files changed, 237 insertions(+), 49 deletions(-)
 create mode 100644 packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/reconnecting_overlay.dart

diff --git a/packages/devtools_app/lib/src/screens/performance/panes/timeline_events/timeline_events_view.dart b/packages/devtools_app/lib/src/screens/performance/panes/timeline_events/timeline_events_view.dart
index 3687b02c914..1a44da58283 100644
--- a/packages/devtools_app/lib/src/screens/performance/panes/timeline_events/timeline_events_view.dart
+++ b/packages/devtools_app/lib/src/screens/performance/panes/timeline_events/timeline_events_view.dart
@@ -3,7 +3,6 @@
 // found in the LICENSE file or at https://developers.google.com/open-source/licenses/bsd.
 
 import 'dart:async';
-import 'dart:math' as math;
 
 import 'package:devtools_app_shared/ui.dart';
 import 'package:devtools_app_shared/utils.dart';
@@ -65,40 +64,21 @@ class _TimelineEventsTabViewState extends State<TimelineEventsTabView>
   }
 
   void _insertOverlay() {
-    final width = math.min(
-      _overlaySize.width,
-      MediaQuery.of(context).size.width - 2 * denseSpacing,
-    );
-    final height = math.min(
-      _overlaySize.height,
-      MediaQuery.of(context).size.height - 2 * denseSpacing,
-    );
     final theme = Theme.of(context);
     _refreshingOverlay?.remove();
     Overlay.of(context).insert(
       _refreshingOverlay = OverlayEntry(
         maintainState: true,
         builder: (context) {
-          return Center(
-            child: Padding(
-              padding: const EdgeInsets.only(top: _overlayOffset),
-              child: RoundedOutlinedBorder(
-                clip: true,
-                child: Container(
-                  width: width,
-                  height: height,
-                  color: theme.colorScheme.semiTransparentOverlayColor,
-                  child: Center(
-                    child: Text(
-                      'Refreshing the timeline...\n\n'
-                      'This may take a few seconds. Please do not\n'
-                      'refresh the page.',
-                      textAlign: TextAlign.center,
-                      style: theme.textTheme.titleMedium,
-                    ),
-                  ),
-                ),
-              ),
+          return DevToolsOverlay(
+            topOffset: _overlayOffset,
+            maxSize: _overlaySize,
+            content: Text(
+              'Refreshing the timeline...\n\n'
+              'This may take a few seconds. Please do not\n'
+              'refresh the page.',
+              textAlign: TextAlign.center,
+              style: theme.textTheme.titleMedium,
             ),
           );
         },
diff --git a/packages/devtools_app/lib/src/shared/editor/editor_client.dart b/packages/devtools_app/lib/src/shared/editor/editor_client.dart
index 8a29cc0e905..e9ee7105463 100644
--- a/packages/devtools_app/lib/src/shared/editor/editor_client.dart
+++ b/packages/devtools_app/lib/src/shared/editor/editor_client.dart
@@ -314,6 +314,27 @@ class EditorClient extends DisposableController
     }
   }
 
+  Future<bool> isClientClosed() async {
+    try {
+      // Make an empty request to DTD.
+      await _dtd.call('', '');
+    } on StateError catch (e) {
+      // TODO(https://github.com/flutter/devtools/issues/9028): Replace with a
+      // check for whether DTD is closed. Requires a change to package:dtd.
+      //
+      // This is only a temporary fix. If the error in package:json_rpc_2 is
+      // changed, this will no longer catch it. See:
+      // https://github.com/dart-lang/tools/blob/b55643dadafd3ac6b2bd20823802f75929ebf98e/pkgs/json_rpc_2/lib/src/client.dart#L151
+      if (e.message.contains('The client is closed.')) {
+        return true;
+      }
+    } catch (e) {
+      // Ignore other exceptions. If the client is open, we expect this to fail
+      // with the error: 'Unknown method "."'.
+    }
+    return false;
+  }
+
   Future<DTDResponse> _call(
     EditorMethod method, {
     Map<String, Object?>? params,
diff --git a/packages/devtools_app/lib/src/shared/ui/common_widgets.dart b/packages/devtools_app/lib/src/shared/ui/common_widgets.dart
index fb8bf822149..20f5610ad8a 100644
--- a/packages/devtools_app/lib/src/shared/ui/common_widgets.dart
+++ b/packages/devtools_app/lib/src/shared/ui/common_widgets.dart
@@ -2283,3 +2283,58 @@ class _PositiveIntegerSettingState extends State<PositiveIntegerSetting>
     );
   }
 }
+
+/// Creates an overlay with the provided [content].
+///
+/// Set [fullScreen] to true to take up the entire screen. Otherwise, a
+/// [maxSize] and [topOffset] can be provided to determine the overlay's size
+/// and location.
+class DevToolsOverlay extends StatelessWidget {
+  const DevToolsOverlay({
+    super.key,
+    required this.content,
+    this.fullScreen = false,
+    this.maxSize,
+    this.topOffset,
+  }) : assert(maxSize != null || topOffset != null ? !fullScreen : true);
+
+  final Widget content;
+  final bool fullScreen;
+  final Size? maxSize;
+  final double? topOffset;
+
+  @override
+  Widget build(BuildContext context) {
+    final parentSize = MediaQuery.of(context).size;
+
+    final overlayContent = Container(
+      width: _overlayWidth(parentSize),
+      height: _overlayHeight(parentSize),
+      color: Theme.of(context).colorScheme.semiTransparentOverlayColor,
+      child: Center(child: content),
+    );
+
+    return fullScreen
+        ? overlayContent
+        : Center(
+          child: Padding(
+            padding: EdgeInsets.only(top: topOffset ?? 0.0),
+            child: RoundedOutlinedBorder(clip: true, child: overlayContent),
+          ),
+        );
+  }
+
+  double _overlayWidth(Size parentSize) {
+    if (fullScreen) return parentSize.width;
+    final defaultWidth = parentSize.width - largeSpacing;
+    return maxSize != null ? min(maxSize!.width, defaultWidth) : defaultWidth;
+  }
+
+  double _overlayHeight(Size parentSize) {
+    if (fullScreen) return parentSize.height;
+    final defaultHeight = parentSize.height - largeSpacing;
+    return maxSize != null
+        ? min(maxSize!.height, defaultHeight)
+        : defaultHeight;
+  }
+}
diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart
index 5f8a493a845..572d1509e41 100644
--- a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file or at https://developers.google.com/open-source/licenses/bsd.
 
+import 'dart:async';
+
 import 'package:devtools_app_shared/utils.dart';
 import 'package:flutter/foundation.dart';
 
@@ -37,17 +39,31 @@ class PropertyEditorController extends DisposableController
       _editableWidgetData;
   final _editableWidgetData = ValueNotifier<EditableWidgetData?>(null);
 
+  ValueListenable<bool> get shouldReconnect => _shouldReconnect;
+  final _shouldReconnect = ValueNotifier<bool>(false);
+
+  bool get waitingForFirstEvent => _waitingForFirstEvent;
+  bool _waitingForFirstEvent = true;
+
   late final Debouncer _editableArgsDebouncer;
 
+  late final Timer _checkConnectionTimer;
+
   static const _editableArgsDebounceDuration = Duration(milliseconds: 600);
 
+  static const _checkConnectionInterval = Duration(minutes: 1);
+
   @override
   void init() {
     super.init();
     _editableArgsDebouncer = Debouncer(duration: _editableArgsDebounceDuration);
+    _checkConnectionTimer = _periodicallyCheckConnection(
+      _checkConnectionInterval,
+    );
 
     autoDisposeStreamSubscription(
       editorClient.activeLocationChangedStream.listen((event) async {
+        if (_waitingForFirstEvent) _waitingForFirstEvent = false;
         final textDocument = event.textDocument;
         final cursorPosition = event.selections.first.active;
         // Don't do anything if the text document is null.
@@ -78,6 +94,7 @@ class PropertyEditorController extends DisposableController
   @override
   void dispose() {
     _editableArgsDebouncer.dispose();
+    _checkConnectionTimer.cancel();
     super.dispose();
   }
 
@@ -121,6 +138,16 @@ class PropertyEditorController extends DisposableController
     );
   }
 
+  Timer _periodicallyCheckConnection(Duration interval) {
+    return Timer.periodic(interval, (timer) async {
+      final isClosed = await editorClient.isClientClosed();
+      if (isClosed) {
+        _shouldReconnect.value = true;
+        timer.cancel();
+      }
+    });
+  }
+
   @visibleForTesting
   void initForTestsOnly({
     EditableArgumentsResult? editableArgsResult,
diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_panel.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_panel.dart
index b0c67e9a554..7cb8ff3b5f1 100644
--- a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_panel.dart
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_panel.dart
@@ -15,6 +15,7 @@ import '../../../shared/editor/editor_client.dart';
 import '../../../shared/ui/common_widgets.dart';
 import 'property_editor_controller.dart';
 import 'property_editor_view.dart';
+import 'reconnecting_overlay.dart';
 
 /// The side panel for the Property Editor.
 class PropertyEditorPanel extends StatefulWidget {
@@ -106,24 +107,36 @@ class _PropertyEditorConnectedPanelState
 
   @override
   Widget build(BuildContext context) {
-    return Scrollbar(
-      controller: scrollController,
-      thumbVisibility: true,
-      child: SingleChildScrollView(
-        controller: scrollController,
-        child: Padding(
-          padding: const EdgeInsets.fromLTRB(
-            denseSpacing,
-            defaultSpacing,
-            defaultSpacing, // Additional right padding for scroll bar.
-            defaultSpacing,
-          ),
-          child: Column(
-            crossAxisAlignment: CrossAxisAlignment.start,
-            children: [PropertyEditorView(controller: widget.controller)],
-          ),
-        ),
-      ),
+    return ValueListenableBuilder<bool>(
+      valueListenable: widget.controller.shouldReconnect,
+      builder: (context, shouldReconnect, _) {
+        return Stack(
+          children: [
+            Scrollbar(
+              controller: scrollController,
+              thumbVisibility: true,
+              child: SingleChildScrollView(
+                controller: scrollController,
+                child: Padding(
+                  padding: const EdgeInsets.fromLTRB(
+                    denseSpacing,
+                    defaultSpacing,
+                    defaultSpacing, // Additional right padding for scroll bar.
+                    defaultSpacing,
+                  ),
+                  child: Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      PropertyEditorView(controller: widget.controller),
+                    ],
+                  ),
+                ),
+              ),
+            ),
+            if (shouldReconnect) const ReconnectingOverlay(),
+          ],
+        );
+      },
     );
   }
 }
diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_view.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_view.dart
index 3db138d8e9e..4007a5436f5 100644
--- a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_view.dart
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_view.dart
@@ -37,8 +37,14 @@ class PropertyEditorView extends StatelessWidget {
 
         final editableWidgetData = values.third as EditableWidgetData?;
         if (editableWidgetData == null) {
-          return const CenteredMessage(
-            message: 'No Flutter widget found at the current cursor location.',
+          final introSentence =
+              controller.waitingForFirstEvent
+                  ? '👋 Welcome to the Flutter Property Editor!'
+                  : 'No Flutter widget found at the current cursor location.';
+          const howToUseSentence =
+              'Please move your cursor to a Flutter widget constructor invocation to view its properties.';
+          return CenteredMessage(
+            message: '$introSentence\n\n$howToUseSentence',
           );
         }
 
diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/reconnecting_overlay.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/reconnecting_overlay.dart
new file mode 100644
index 00000000000..66f9f3394b2
--- /dev/null
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/reconnecting_overlay.dart
@@ -0,0 +1,71 @@
+// Copyright 2025 The Flutter Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file or at https://developers.google.com/open-source/licenses/bsd.
+
+import 'dart:async';
+
+import 'package:devtools_app_shared/ui.dart';
+import 'package:flutter/material.dart';
+
+import '../../../shared/ui/common_widgets.dart';
+import 'utils/utils.dart';
+
+class ReconnectingOverlay extends StatefulWidget {
+  const ReconnectingOverlay({super.key});
+
+  @override
+  State<ReconnectingOverlay> createState() => _ReconnectingOverlayState();
+}
+
+class _ReconnectingOverlayState extends State<ReconnectingOverlay> {
+  static const _countdownInterval = Duration(seconds: 1);
+  late final Timer _countdownTimer;
+  int _secondsUntilReconnection = 3;
+
+  @override
+  void initState() {
+    super.initState();
+    _countdownTimer = Timer.periodic(_countdownInterval, _onTick);
+  }
+
+  @override
+  void dispose() {
+    _countdownTimer.cancel();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    return DevToolsOverlay(
+      fullScreen: true,
+      content: Column(
+        mainAxisAlignment: MainAxisAlignment.center,
+        children: [
+          const CircularProgressIndicator(),
+          const SizedBox(height: defaultSpacing),
+          Text(
+            _secondsUntilReconnection > 0
+                ? 'Reconnecting in $_secondsUntilReconnection'
+                : 'Reconnecting...',
+            style: theme.textTheme.headlineMedium,
+          ),
+        ],
+      ),
+    );
+  }
+
+  void _onTick(Timer timer) {
+    setState(() {
+      _secondsUntilReconnection--;
+      if (_secondsUntilReconnection == 0) {
+        timer.cancel();
+        _reconnect();
+      }
+    });
+  }
+
+  void _reconnect() {
+    forceReload();
+  }
+}
diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/_utils_desktop.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/_utils_desktop.dart
index c79da0f1bac..ff2333a299b 100644
--- a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/_utils_desktop.dart
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/_utils_desktop.dart
@@ -2,6 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file or at https://developers.google.com/open-source/licenses/bsd.
 
+void reloadIframe() {
+  // No-op for desktop platforms.
+}
+
 void addBlurListener() {
   // No-op for desktop platforms.
 }
diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/_utils_web.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/_utils_web.dart
index 87b99146ce0..880e275da9c 100644
--- a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/_utils_web.dart
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/_utils_web.dart
@@ -6,6 +6,10 @@ import 'dart:js_interop';
 
 import 'package:web/web.dart';
 
+void reloadIframe() {
+  window.location.reload();
+}
+
 void addBlurListener() {
   window.addEventListener('blur', _onBlur.toJS);
 }
diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/utils.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/utils.dart
index f33d9789fa5..fa3f1d7e3a7 100644
--- a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/utils.dart
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/utils.dart
@@ -78,6 +78,13 @@ RichText convertDartDocToRichText(
   return RichText(text: TextSpan(children: children));
 }
 
+/// Workaround to force reload the Property Editor when it disconnects.
+///
+/// See https://github.com/flutter/devtools/issues/9028 for details.
+void forceReload() {
+  reloadIframe();
+}
+
 /// Workaround to prevent TextFields from holding onto focus when IFRAME-ed.
 ///
 /// See https://github.com/flutter/devtools/issues/8929 for details.

From 798a83f5707248aa9a571e0d7652b9bca75b61d2 Mon Sep 17 00:00:00 2001
From: Elliott Brooks <21270878+elliette@users.noreply.github.com>
Date: Tue, 25 Mar 2025 11:11:01 -0700
Subject: [PATCH 3/6] Update to patch version

---
 packages/devtools_app/lib/devtools.dart | 2 +-
 packages/devtools_app/pubspec.yaml      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/devtools_app/lib/devtools.dart b/packages/devtools_app/lib/devtools.dart
index 0da9cf9190f..69b0fb1fc14 100644
--- a/packages/devtools_app/lib/devtools.dart
+++ b/packages/devtools_app/lib/devtools.dart
@@ -10,4 +10,4 @@
 /// Note: a regexp in the `dt update-version' command logic matches the constant
 /// declaration `const version =`. If you change the declaration you must also
 /// modify the regex in the `dt update-version' command logic.
-const version = '2.44.0';
+const version = '2.44.1';
diff --git a/packages/devtools_app/pubspec.yaml b/packages/devtools_app/pubspec.yaml
index 8e027f80a4c..d6e9a7d24ad 100644
--- a/packages/devtools_app/pubspec.yaml
+++ b/packages/devtools_app/pubspec.yaml
@@ -7,7 +7,7 @@ publish_to: none
 
 # Note: this version should only be updated by running the 'dt update-version'
 # command that updates the version here and in 'devtools.dart'.
-version: 2.44.0
+version: 2.44.1
 
 repository: https://github.com/flutter/devtools/tree/master/packages/devtools_app
 

From 82ac072204abfbdee461d71b566d7d0906508a81 Mon Sep 17 00:00:00 2001
From: Elliott Brooks <21270878+elliette@users.noreply.github.com>
Date: Tue, 1 Apr 2025 10:47:40 -0700
Subject: [PATCH 4/6] Update property_editor_controller.dart

---
 .../ide_shared/property_editor/property_editor_controller.dart   | 1 -
 1 file changed, 1 deletion(-)

diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart
index 30f1f512aff..ac4ed486a7f 100644
--- a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/property_editor_controller.dart
@@ -95,7 +95,6 @@ class PropertyEditorController extends DisposableController
             cursorPosition == _currentCursorPosition) {
           return;
         }
-        
         if (!textDocument.uriAsString.endsWith('.dart')) {
           _editableWidgetData.value = (
             properties: [],

From 1deb82d2232ca2ee13d286d88881b48c675f9419 Mon Sep 17 00:00:00 2001
From: Elliott Brooks <21270878+elliette@users.noreply.github.com>
Date: Tue, 1 Apr 2025 10:49:00 -0700
Subject: [PATCH 5/6] Update editor_client.dart

---
 .../lib/src/shared/editor/editor_client.dart  | 21 -------------------
 1 file changed, 21 deletions(-)

diff --git a/packages/devtools_app/lib/src/shared/editor/editor_client.dart b/packages/devtools_app/lib/src/shared/editor/editor_client.dart
index 839cea0d22c..9d55c021864 100644
--- a/packages/devtools_app/lib/src/shared/editor/editor_client.dart
+++ b/packages/devtools_app/lib/src/shared/editor/editor_client.dart
@@ -319,27 +319,6 @@ class EditorClient extends DisposableController
     }
   }
 
-  Future<bool> isClientClosed() async {
-    try {
-      // Make an empty request to DTD.
-      await _dtd.call('', '');
-    } on StateError catch (e) {
-      // TODO(https://github.com/flutter/devtools/issues/9028): Replace with a
-      // check for whether DTD is closed. Requires a change to package:dtd.
-      //
-      // This is only a temporary fix. If the error in package:json_rpc_2 is
-      // changed, this will no longer catch it. See:
-      // https://github.com/dart-lang/tools/blob/b55643dadafd3ac6b2bd20823802f75929ebf98e/pkgs/json_rpc_2/lib/src/client.dart#L151
-      if (e.message.contains('The client is closed.')) {
-        return true;
-      }
-    } catch (e) {
-      // Ignore other exceptions. If the client is open, we expect this to fail
-      // with the error: 'Unknown method "."'.
-    }
-    return false;
-  }
-
   Future<DTDResponse> _call(
     EditorMethod method, {
     Map<String, Object?>? params,

From c27d4823f2c1a4b1a06ba4e9f2bfa4d0d5ee0d97 Mon Sep 17 00:00:00 2001
From: Elliott Brooks <21270878+elliette@users.noreply.github.com>
Date: Tue, 1 Apr 2025 10:49:40 -0700
Subject: [PATCH 6/6] Update utils.dart

---
 .../ide_shared/property_editor/utils/utils.dart            | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/utils.dart b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/utils.dart
index 1e52d2845b0..4c05833f7d5 100644
--- a/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/utils.dart
+++ b/packages/devtools_app/lib/src/standalone_ui/ide_shared/property_editor/utils/utils.dart
@@ -142,13 +142,6 @@ void forceReload() {
   reloadIframe();
 }
 
-/// Workaround to force reload the Property Editor when it disconnects.
-///
-/// See https://github.com/flutter/devtools/issues/9028 for details.
-void forceReload() {
-  reloadIframe();
-}
-
 /// Workaround to prevent TextFields from holding onto focus when IFRAME-ed.
 ///
 /// See https://github.com/flutter/devtools/issues/8929 for details.