[PTRun]Fix search being abandoned while cycling results (#27409)

* [Launcher] ignoring key preses while previous key press processing is ongoing

* extending TextChangedEventArgs with Initiator, storing and using initiator for the event lifetime to avoid overwriting of the initiator when parallel events occur.

* extending code with check on event object presence

src/modules/launcher/PowerLauncher/MainWindow.xaml.cs

@@ -218,14 +218,15 @@ namespace PowerLauncher
 
             if (showResultsWithDelay)
             {
-                _reactiveSubscription = Observable.FromEventPattern<TextChangedEventHandler, TextChangedEventArgs>(
+                _reactiveSubscription = Observable.FromEventPattern<TextChangedEventHandler, TextChangedEventWithInitiatorArgs>(
+                    conversion => (sender, eventArg) => conversion(sender, new TextChangedEventWithInitiatorArgs(eventArg.RoutedEvent, eventArg.UndoAction)),
                     add => SearchBox.QueryTextBox.TextChanged += add,
                     remove => SearchBox.QueryTextBox.TextChanged -= remove)
-                    .Do(@event => ClearAutoCompleteText((TextBox)@event.Sender))
+                    .Do(@event => ClearAutoCompleteText((TextBox)@event.Sender, @event))
                     .Throttle(TimeSpan.FromMilliseconds(_settings.SearchInputDelayFast))
-                    .Do(@event => Dispatcher.InvokeAsync(() => PerformSearchQuery((TextBox)@event.Sender, false)))
+                    .Do(@event => Dispatcher.InvokeAsync(() => PerformSearchQuery((TextBox)@event.Sender, false, @event)))
                     .Throttle(TimeSpan.FromMilliseconds(_settings.SearchInputDelay))
-                    .Do(@event => Dispatcher.InvokeAsync(() => PerformSearchQuery((TextBox)@event.Sender, true)))
+                    .Do(@event => Dispatcher.InvokeAsync(() => PerformSearchQuery((TextBox)@event.Sender, true, @event)))
                     .Subscribe();
 
                 /*
@@ -358,10 +359,18 @@ namespace PowerLauncher
                 _isTextSetProgrammatically = true;
                 if (_viewModel.Results != null)
                 {
-                    SearchBox.QueryTextBox.Text = MainViewModel.GetSearchText(
+                    string newText = MainViewModel.GetSearchText(
                         _viewModel.Results.SelectedIndex,
                         _viewModel.SystemQueryText,
                         _viewModel.QueryText);
+                    if (SearchBox.QueryTextBox.Text != newText)
+                    {
+                        SearchBox.QueryTextBox.Text = newText;
+                    }
+                    else
+                    {
+                        _isTextSetProgrammatically = false;
+                    }
                 }
             }
         }
@@ -563,12 +572,18 @@ namespace PowerLauncher
         private void QueryTextBox_TextChanged(object sender, TextChangedEventArgs e)
         {
             var textBox = (TextBox)sender;
-            ClearAutoCompleteText(textBox);
+            ClearAutoCompleteText(textBox, null);
             PerformSearchQuery(textBox);
         }
 
-        private void ClearAutoCompleteText(TextBox textBox)
+        private void ClearAutoCompleteText(TextBox textBox, System.Reactive.EventPattern<TextChangedEventWithInitiatorArgs> @event)
         {
+            bool isTextSetProgrammaticallyAtStart = _isTextSetProgrammatically;
+            if (@event != null)
+            {
+                @event.EventArgs.IsTextSetProgrammatically = isTextSetProgrammaticallyAtStart;
+            }
+
             var text = textBox.Text;
             var autoCompleteText = SearchBox.AutoCompleteTextBlock.Text;
 
@@ -588,7 +603,7 @@ namespace PowerLauncher
                 if (pTRunStartNewSearchAction == "DeSelect")
                 {
                     // leave the results, be deselect anything to it will not be activated by <enter> key, can still be arrow-key or clicked though
-                    if (!_isTextSetProgrammatically)
+                    if (!isTextSetProgrammaticallyAtStart)
                     {
                         DeselectAllResults();
                     }
@@ -596,7 +611,7 @@ namespace PowerLauncher
                 else if (pTRunStartNewSearchAction == "Clear")
                 {
                     // remove all results to prepare for new results, this causes flashing usually and is not cool
-                    if (!_isTextSetProgrammatically)
+                    if (!isTextSetProgrammaticallyAtStart)
                     {
                         ClearResults();
                     }
@@ -630,14 +645,20 @@ namespace PowerLauncher
 
         private void PerformSearchQuery(TextBox textBox)
         {
-            PerformSearchQuery(textBox, null);
+            PerformSearchQuery(textBox, null, null);
         }
 
-        private void PerformSearchQuery(TextBox textBox, bool? delayedExecution)
+        private void PerformSearchQuery(TextBox textBox, bool? delayedExecution, System.Reactive.EventPattern<TextChangedEventWithInitiatorArgs> @event)
         {
             var text = textBox.Text;
+            bool isTextSetProgrammaticallyForEvent = _isTextSetProgrammatically;
 
-            if (_isTextSetProgrammatically)
+            if (@event != null)
+            {
+                isTextSetProgrammaticallyForEvent = @event.EventArgs.IsTextSetProgrammatically;
+            }
+
+            if (isTextSetProgrammaticallyForEvent)
             {
                 textBox.SelectionStart = textBox.Text.Length;
 

src/modules/launcher/PowerLauncher/TextChangedEventWithInitiatorArgs.cs

@@ -0,0 +1,24 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows;
+using System.Windows.Controls;
+
+namespace PowerLauncher
+{
+    internal sealed class TextChangedEventWithInitiatorArgs : TextChangedEventArgs
+    {
+        public TextChangedEventWithInitiatorArgs(RoutedEvent id, UndoAction action)
+            : base(id, action)
+        {
+        }
+
+        public bool IsTextSetProgrammatically { get; set; }
+    }
+}