Fix copy to clipboard STA thread issue

Author: Jack251970

Flow.Launcher.Infrastructure/NativeMethods.txt

@@ -16,4 +16,7 @@ WM_KEYUP
 WM_SYSKEYDOWN
 WM_SYSKEYUP
 
-EnumWindows
+EnumWindows
+
+OleInitialize
+OleUninitialize

Flow.Launcher.Infrastructure/UserSettings/Settings.cs

@@ -248,7 +248,7 @@ public SearchPrecisionScore QuerySearchPrecision
         [JsonIgnore]
         public ObservableCollection<BuiltinShortcutModel> BuiltinShortcuts { get; set; } = new()
         {
-            new BuiltinShortcutModel("{clipboard}", "shortcut_clipboard_description", Clipboard.GetText),
+            new BuiltinShortcutModel("{clipboard}", "shortcut_clipboard_description", () => Win32Helper.StartSTATaskAsync(Clipboard.GetText).Result),
             new BuiltinShortcutModel("{active_explorer_path}", "shortcut_active_explorer_path", FileExplorerHelper.GetActiveExplorerPath)
         };
 

Flow.Launcher.Infrastructure/Win32Helper.cs

@@ -2,6 +2,9 @@
 using System.Runtime.InteropServices;
 using System.Windows.Interop;
 using System.Windows;
+using System.Threading.Tasks;
+using System.Threading;
+using Windows.Win32;
 
 namespace Flow.Launcher.Infrastructure
 {
@@ -97,5 +100,77 @@ private static void SetWindowAccent(Window w, AccentState state)
             Marshal.FreeHGlobal(accentPtr);
         }
         #endregion
+
+        #region STA Thread
+
+        /*
+        Found on https://github.com/files-community/Files
+        */
+
+        public static Task StartSTATaskAsync(Action action)
+        {
+            var taskCompletionSource = new TaskCompletionSource();
+            Thread thread = new(() =>
+            {
+                PInvoke.OleInitialize();
+
+                try
+                {
+                    action();
+                    taskCompletionSource.SetResult();
+                }
+                catch (System.Exception)
+                {
+                    taskCompletionSource.SetResult();
+                }
+                finally
+                {
+                    PInvoke.OleUninitialize();
+                }
+            })
+            {
+                IsBackground = true,
+                Priority = ThreadPriority.Normal
+            };
+
+            thread.SetApartmentState(ApartmentState.STA);
+            thread.Start();
+
+            return taskCompletionSource.Task;
+        }
+
+        public static Task<T> StartSTATaskAsync<T>(Func<T> func)
+        {
+            var taskCompletionSource = new TaskCompletionSource<T>();
+
+            Thread thread = new(() =>
+            {
+                PInvoke.OleInitialize();
+
+                try
+                {
+                    taskCompletionSource.SetResult(func());
+                }
+                catch (System.Exception)
+                {
+                    taskCompletionSource.SetResult(default);
+                }
+                finally
+                {
+                    PInvoke.OleUninitialize();
+                }
+            })
+            {
+                IsBackground = true,
+                Priority = ThreadPriority.Normal
+            };
+
+            thread.SetApartmentState(ApartmentState.STA);
+            thread.Start();
+
+            return taskCompletionSource.Task;
+        }
+
+        #endregion
     }
 }

Flow.Launcher/Languages/en.xaml

@@ -336,6 +336,7 @@
     <system:String x:Key="newActionKeywordsHasBeenAssigned">This new Action Keyword is already assigned to another plugin, please choose a different one</system:String>
     <system:String x:Key="success">Success</system:String>
     <system:String x:Key="completedSuccessfully">Completed successfully</system:String>
+    <system:String x:Key="failedToCopy">Failed to copy</system:String>
     <system:String x:Key="actionkeyword_tips">Enter the action keyword you like to use to start the plugin. Use * if you don't want to specify any, and the plugin will be triggered without any action keywords.</system:String>
 
     <!--  Custom Query Hotkey Dialog  -->

Flow.Launcher/PublicAPIInstance.cs

@@ -118,37 +118,91 @@ public void ShellRun(string cmd, string filename = "cmd.exe")
             ShellCommand.Execute(startInfo);
         }
 
-        public void CopyToClipboard(string stringToCopy, bool directCopy = false, bool showDefaultNotification = true)
+        public async void CopyToClipboard(string stringToCopy, bool directCopy = false, bool showDefaultNotification = true)
         {
             if (string.IsNullOrEmpty(stringToCopy))
+            {
                 return;
+            }
 
             var isFile = File.Exists(stringToCopy);
             if (directCopy && (isFile || Directory.Exists(stringToCopy)))
             {
-                var paths = new StringCollection
+                // Sometimes the clipboard is locked and cannot be accessed,
+                // we need to retry a few times before giving up
+                var exception = await RetryActionOnSTAThreadAsync(() =>
+                {
+                    var paths = new StringCollection
                     {
                         stringToCopy
                     };
 
-                Clipboard.SetFileDropList(paths);
-
-                if (showDefaultNotification)
-                    ShowMsg(
-                        $"{GetTranslation("copy")} {(isFile ? GetTranslation("fileTitle") : GetTranslation("folderTitle"))}",
-                        GetTranslation("completedSuccessfully"));
+                    Clipboard.SetFileDropList(paths);
+                });
+                
+                if (exception == null)
+                {
+                    if (showDefaultNotification)
+                    {
+                        ShowMsg(
+                            $"{GetTranslation("copy")} {(isFile ? GetTranslation("fileTitle") : GetTranslation("folderTitle"))}",
+                            GetTranslation("completedSuccessfully"));
+                    }
+                }
+                else
+                {
+                    LogException(nameof(PublicAPIInstance), "Failed to copy file/folder to clipboard", exception);
+                    ShowMsgError(GetTranslation("failedToCopy"));
+                }
             }
             else
             {
-                Clipboard.SetDataObject(stringToCopy);
+                // Sometimes the clipboard is locked and cannot be accessed,
+                // we need to retry a few times before giving up
+                var exception = await RetryActionOnSTAThreadAsync(() =>
+                {
+                    // We shouold use SetText instead of SetDataObject to avoid the clipboard being locked by other applications
+                    Clipboard.SetText(stringToCopy);
+                });
 
-                if (showDefaultNotification)
-                    ShowMsg(
-                        $"{GetTranslation("copy")} {GetTranslation("textTitle")}",
-                        GetTranslation("completedSuccessfully"));
+                if (exception == null)
+                {
+                    if (showDefaultNotification)
+                    {
+                        ShowMsg(
+                            $"{GetTranslation("copy")} {GetTranslation("textTitle")}",
+                            GetTranslation("completedSuccessfully"));
+                    }
+                }
+                else
+                {
+                    LogException(nameof(PublicAPIInstance), "Failed to copy text to clipboard", exception);
+                    ShowMsgError(GetTranslation("failedToCopy"));
+                }  
             }
         }
 
+        private static async Task<Exception> RetryActionOnSTAThreadAsync(Action action, int retryCount = 6, int retryDelay = 150)
+        {
+            for (var i = 0; i < retryCount; i++)
+            {
+                try
+                {
+                    await Win32Helper.StartSTATaskAsync(action);
+                    break;
+                }
+                catch (Exception e)
+                {
+                    if (i == retryCount - 1)
+                    {
+                        return e;
+                    }
+                    await Task.Delay(retryDelay);
+                }
+            }
+            return null;
+        }
+
         public void StartLoadingBar() => _mainVM.ProgressBarVisibility = Visibility.Visible;
 
         public void StopLoadingBar() => _mainVM.ProgressBarVisibility = Visibility.Collapsed;