Improve code quality & Improve code comments

Author: Jack251970

Flow.Launcher/PublicAPIInstance.cs

@@ -2,6 +2,7 @@
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Collections.Specialized;
+using System.ComponentModel;
 using System.Diagnostics;
 using System.IO;
 using System.Linq;
@@ -10,6 +11,7 @@
 using System.Threading;
 using System.Threading.Tasks;
 using System.Windows;
+using System.Windows.Input;
 using System.Windows.Media;
 using CommunityToolkit.Mvvm.DependencyInjection;
 using Flow.Launcher.Core;
@@ -32,8 +34,6 @@
 using JetBrains.Annotations;
 using Squirrel;
 using Stopwatch = Flow.Launcher.Infrastructure.Stopwatch;
-using System.ComponentModel;
-using System.Windows.Input;
 
 namespace Flow.Launcher
 {
@@ -93,18 +93,8 @@ public async void RestartApp()
         }
 
         public void ShowMainWindow() => _mainVM.Show();
-        
-        public void FocusQueryTextBox()
-        {
-            Application.Current.Dispatcher.Invoke(new Action(() =>
-            {
-                if (Application.Current.MainWindow is MainWindow mw)
-                {
-                    mw.QueryTextBox.Focus();
-                    Keyboard.Focus(mw.QueryTextBox);
-                }
-            }));
-        }
+
+        public void FocusQueryTextBox() => _mainVM.FocusQueryTextBox();
 
         public void HideMainWindow() => _mainVM.Hide();
 

Flow.Launcher/ViewModel/MainViewModel.cs

@@ -1926,6 +1926,21 @@ public void UpdateResultView(ICollection<ResultsForUpdate> resultsForUpdates)
             Results.AddResults(resultsForUpdates, token, reSelect);
         }
 
+        [System.Diagnostics.CodeAnalysis.SuppressMessage("Performance", "CA1822:Mark members as static", Justification = "<Pending>")]
+        public void FocusQueryTextBox()
+        {
+            // When application is exiting, the Application.Current will be null
+            Application.Current?.Dispatcher.Invoke(() =>
+            {
+                // When application is exiting, the Application.Current will be null
+                if (Application.Current?.MainWindow is MainWindow window)
+                {
+                    window.QueryTextBox.Focus();
+                    Keyboard.Focus(window.QueryTextBox);
+                }
+            });
+        }
+
         #endregion
 
         #region IDisposable

Plugins/Flow.Launcher.Plugin.Shell/Main.cs

@@ -382,10 +382,13 @@ private void OnWinRPressed()
             // show the main window and set focus to the query box
             _ = Task.Run(async () =>
             {
-                await Task.Delay(50);  // 💡 키보드 이벤트 처리가 끝난 뒤
-                Context.API.FocusQueryTextBox();
-
                 Context.API.ChangeQuery($"{Context.CurrentPluginMetadata.ActionKeywords[0]}{Plugin.Query.TermSeparator}");
+
+                // Win+R is a system-reserved shortcut, and though the plugin intercepts the keyboard event and
+                // shows the main window, Windows continues to process the Win key and briefly reclaims focus.
+                // So we need to wait until the keyboard event processing is completed and then set focus
+                await Task.Delay(50);
+                Context.API.FocusQueryTextBox();
             });
         }