Response to all selectionchanged event by using a task

QuickLook/FocusMonitor.cs

@@ -0,0 +1,63 @@
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using QuickLook.Helpers;
+
+namespace QuickLook
+{
+    internal class FocusMonitor
+    {
+        public delegate void FocusedItemChangedEventHandler(FocusedItemChangedEventArgs e);
+
+        private static FocusMonitor _instance;
+
+        public bool IsRunning { get; private set; }
+
+        public event FocusedItemChangedEventHandler FocusedItemChanged;
+
+        public void Start()
+        {
+            IsRunning = true;
+
+            new Task(() =>
+            {
+                var currentPath = NativeMethods.QuickLook.GetCurrentSelectionFirst();
+
+                while (IsRunning)
+                {
+                    Thread.Sleep(500);
+
+                    if (WindowHelper.IsFocusedControlExplorerItem())
+                    {
+                        var file = NativeMethods.QuickLook.GetCurrentSelectionFirst();
+                        if (file != currentPath)
+                        {
+                            FocusedItemChanged?.Invoke(new FocusedItemChangedEventArgs(file));
+                            currentPath = file;
+                        }
+                    }
+                }
+            }).Start();
+        }
+
+        public void Stop()
+        {
+            IsRunning = false;
+        }
+
+        internal static FocusMonitor GetInstance()
+        {
+            return _instance ?? (_instance = new FocusMonitor());
+        }
+    }
+
+    internal class FocusedItemChangedEventArgs : EventArgs
+    {
+        public FocusedItemChangedEventArgs(string files)
+        {
+            FocusedFile = files;
+        }
+
+        public string FocusedFile { get; }
+    }
+}

QuickLook/Helpers/AutoStartupHelper.cs

@@ -1,7 +1,7 @@
 using System;
 using System.IO;
 using System.Runtime.InteropServices.ComTypes;
-using QuickLook.NativeMethods;
+using QuickLook.NativeMethods.Shell32;
 
 namespace QuickLook.Helpers
 {

QuickLook/Helpers/FileHelper.cs

@@ -5,7 +5,7 @@ using System.IO;
 using System.Linq;
 using System.Runtime.InteropServices;
 using System.Text;
-using QuickLook.NativeMethods;
+using QuickLook.NativeMethods.Shell32;
 
 namespace QuickLook.Helpers
 {

QuickLook/MainWindowTransparent.xaml.cs

@@ -2,6 +2,7 @@
 using System.Diagnostics;
 using System.IO;
 using System.Windows;
+using System.Windows.Forms;
 using System.Windows.Threading;
 using QuickLook.Helpers;
 using QuickLook.Helpers.BlurLibrary;
@@ -42,7 +43,8 @@ namespace QuickLook
                     OpenWithAssocApp();
             };*/
 
-            buttonOpenWith.Click += (sender, e) => RunAndClose();
+            buttonOpenWith.Click += (sender, e) => ViewWindowManager.GetInstance()
+                .InvokeRoutine(new KeyEventArgs(Keys.Escape));
         }
 
         public ContextObject ContextObject { get; private set; }

QuickLook/NativeMethods/QuickLook.cs

@@ -1,5 +1,7 @@
-using System.Runtime.InteropServices;
+using System.Linq;
+using System.Runtime.InteropServices;
 using System.Text;
+using System.Threading.Tasks;
 
 namespace QuickLook.NativeMethods
 {
@@ -16,5 +18,30 @@ namespace QuickLook.NativeMethods
 
         [DllImport("QuickLook.Native.Shell32.dll", CallingConvention = CallingConvention.Cdecl)]
         internal static extern void GetCurrentSelectionBuffer([MarshalAs(UnmanagedType.LPWStr)] StringBuilder buffer);
+
+        internal static string[] GetCurrentSelection()
+        {
+            StringBuilder sb = null;
+            // communicate with COM in a separate thread
+            Task.Run(() =>
+            {
+                SaveCurrentSelection();
+
+                var n = GetCurrentSelectionCount();
+                if (n != 0)
+                {
+                    sb = new StringBuilder(n * 261); // MAX_PATH + NULL = 261
+                    GetCurrentSelectionBuffer(sb);
+                }
+            }).Wait();
+            return sb == null || sb.Length == 0 ? new string[0] : sb.ToString().Split('|');
+        }
+
+        internal static string GetCurrentSelectionFirst()
+        {
+            var files = GetCurrentSelection();
+
+            return files.Any() ? files.First() : string.Empty;
+        }
     }
 }

QuickLook/NativeMethods/Shell32/IShellLink.cs

@@ -2,14 +2,8 @@
 using System.Runtime.InteropServices;
 using System.Text;
 
-namespace QuickLook.NativeMethods
+namespace QuickLook.NativeMethods.Shell32
 {
-    [ComImport]
-    [Guid("00021401-0000-0000-C000-000000000046")]
-    internal class ShellLink
-    {
-    }
-
     [ComImport]
     [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
     [Guid("000214F9-0000-0000-C000-000000000046")]
@@ -42,36 +36,4 @@ namespace QuickLook.NativeMethods
         void Resolve(IntPtr hwnd, int fFlags);
         void SetPath([MarshalAs(UnmanagedType.LPWStr)] string pszFile);
     }
-
-    [ComImport]
-    [Guid("72C24DD5-D70A-438B-8A42-98424B88AFB8")]
-    internal class WshShell
-    {
-    }
-
-    [ComImport]
-    [InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]
-    [Guid("F935DC21-1CF0-11D0-ADB9-00C04FD58A0B")]
-    internal interface IWshShell
-    {
-        IWshShortcut CreateShortcut(string pathLink);
-    }
-
-    [ComImport]
-    [InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]
-    [Guid("F935DC23-1CF0-11D0-ADB9-00C04FD58A0B")]
-    internal interface IWshShortcut
-    {
-        string FullName { get; }
-        string Arguments { get; set; }
-        string Description { get; set; }
-        string Hotkey { get; set; }
-        string IconLocation { get; set; }
-        string RelativePath { set; }
-        string TargetPath { get; set; }
-        int WindowStyle { get; set; }
-        string WorkingDirectory { get; set; }
-        void Load([In] string pathLink);
-        void Save();
-    }
 }

QuickLook/NativeMethods/Shell32/IWshShell.cs

@@ -0,0 +1,12 @@
+using System.Runtime.InteropServices;
+
+namespace QuickLook.NativeMethods.Shell32
+{
+    [ComImport]
+    [InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]
+    [Guid("F935DC21-1CF0-11D0-ADB9-00C04FD58A0B")]
+    internal interface IWshShell
+    {
+        IWshShortcut CreateShortcut(string pathLink);
+    }
+}

QuickLook/NativeMethods/Shell32/IWshShortcut.cs

@@ -0,0 +1,22 @@
+using System.Runtime.InteropServices;
+
+namespace QuickLook.NativeMethods.Shell32
+{
+    [ComImport]
+    [InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]
+    [Guid("F935DC23-1CF0-11D0-ADB9-00C04FD58A0B")]
+    internal interface IWshShortcut
+    {
+        string FullName { get; }
+        string Arguments { get; set; }
+        string Description { get; set; }
+        string Hotkey { get; set; }
+        string IconLocation { get; set; }
+        string RelativePath { set; }
+        string TargetPath { get; set; }
+        int WindowStyle { get; set; }
+        string WorkingDirectory { get; set; }
+        void Load([In] string pathLink);
+        void Save();
+    }
+}

QuickLook/NativeMethods/Shell32/ShellLink.cs

@@ -0,0 +1,10 @@
+using System.Runtime.InteropServices;
+
+namespace QuickLook.NativeMethods.Shell32
+{
+    [ComImport]
+    [Guid("00021401-0000-0000-C000-000000000046")]
+    internal class ShellLink
+    {
+    }
+}

QuickLook/NativeMethods/Shell32/WshShell.cs

@@ -0,0 +1,10 @@
+using System.Runtime.InteropServices;
+
+namespace QuickLook.NativeMethods.Shell32
+{
+    [ComImport]
+    [Guid("72C24DD5-D70A-438B-8A42-98424B88AFB8")]
+    internal class WshShell
+    {
+    }
+}

QuickLook/QuickLook.csproj

@@ -83,6 +83,7 @@
     <Compile Include="Converters\BooleanToResizeModeConverter.cs" />
     <Compile Include="Converters\BooleanToVisibilityCollapsedConverter.cs" />
     <Compile Include="Converters\BooleanToResizeBorderThicknessConverter.cs" />
+    <Compile Include="FocusMonitor.cs" />
     <Compile Include="Helpers\AutoStartupHelper.cs" />
     <Compile Include="Controls\BackgroundVisualHost.cs" />
     <Compile Include="Controls\BusyDecorator.cs" />
@@ -108,7 +109,11 @@
     <Compile Include="Helpers\BlurLibrary\PlatformsImpl\WindowsVistaWindowBlurController.cs" />
     <Compile Include="Helpers\FileHelper.cs" />
     <Compile Include="MainWindowNoTransparent.cs" />
-    <Compile Include="NativeMethods\ShellLink.cs" />
+    <Compile Include="NativeMethods\Shell32\IShellLink.cs" />
+    <Compile Include="NativeMethods\Shell32\IWshShell.cs" />
+    <Compile Include="NativeMethods\Shell32\IWshShortcut.cs" />
+    <Compile Include="NativeMethods\Shell32\ShellLink.cs" />
+    <Compile Include="NativeMethods\Shell32\WshShell.cs" />
     <Compile Include="PidHelper.cs" />
     <Compile Include="PluginManager.cs" />
     <Compile Include="Plugin\InfoPanel\DpiHelpers.cs" />

QuickLook/ViewWindowManager.cs

@@ -1,9 +1,6 @@
 using System;
 using System.Diagnostics;
 using System.IO;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 using System.Windows;
 using System.Windows.Forms;
 using QuickLook.Helpers;
@@ -14,11 +11,13 @@ namespace QuickLook
     internal class ViewWindowManager
     {
         private static ViewWindowManager _instance;
+
         private readonly MainWindowNoTransparent _viewWindowNoTransparent;
         private readonly MainWindowTransparent _viewWindowTransparentTransparent;
-
         private MainWindowTransparent _currentMainWindow;
 
+        private string _path = string.Empty;
+
         internal ViewWindowManager()
         {
             _viewWindowTransparentTransparent = new MainWindowTransparent();
@@ -43,17 +42,17 @@ namespace QuickLook
                     TogglePreview(kea);
                     break;
                 case Keys.Escape:
-                    ClosePreview(kea, false);
+                    ClosePreview(kea);
                     break;
                 case Keys.Enter:
-                    ClosePreview(kea, true);
+                    RunAndClosePreview(kea);
                     break;
                 default:
                     break;
             }
         }
 
-        private void ClosePreview(KeyEventArgs kea, bool runBeforeClose)
+        private void RunAndClosePreview(KeyEventArgs kea = null)
         {
             if (!WindowHelper.IsFocusedControlExplorerItem() && !WindowHelper.IsFocusedWindowSelf())
                 return;
@@ -61,26 +60,40 @@ namespace QuickLook
             if (_currentMainWindow.Visibility != Visibility.Visible)
                 return;
 
-            if (runBeforeClose)
+            StopFocusMonitor();
-                _currentMainWindow.RunAndClose();
+            _currentMainWindow.RunAndClose();
-            else
+            if (kea != null)
-                _currentMainWindow.BeginHide();
+                kea.Handled = true;
-            kea.Handled = true;
         }
 
-        private void TogglePreview(KeyEventArgs kea)
+        internal void ClosePreview(KeyEventArgs kea = null)
+        {
+            StopFocusMonitor();
+            _currentMainWindow.BeginHide();
+
+            if (kea != null)
+                kea.Handled = true;
+        }
+
+        private void TogglePreview(KeyEventArgs kea = null)
         {
             if (!WindowHelper.IsFocusedControlExplorerItem() && !WindowHelper.IsFocusedWindowSelf())
                 return;
 
             if (_currentMainWindow.Visibility == Visibility.Visible)
-                _currentMainWindow.BeginHide();
+            {
+                ClosePreview();
+            }
             else
-                InvokeViewer(GetCurrentSelection());
+            {
-            kea.Handled = true;
+                _path = NativeMethods.QuickLook.GetCurrentSelectionFirst();
+                InvokeViewer();
+            }
+            if (kea != null)
+                kea.Handled = true;
         }
 
-        private void SwitchPreview(KeyEventArgs kea)
+        private void SwitchPreview(KeyEventArgs kea = null)
         {
             if (_currentMainWindow.Visibility != Visibility.Visible)
                 return;
@@ -88,21 +101,72 @@ namespace QuickLook
             if (!WindowHelper.IsFocusedControlExplorerItem())
                 return;
 
-            _currentMainWindow.UnloadPlugin();
+            _path = NativeMethods.QuickLook.GetCurrentSelectionFirst();
-            InvokeViewer(GetCurrentSelection());
+
-            kea.Handled = false;
+            InvokeViewer();
+            if (kea != null)
+                kea.Handled = false;
         }
 
-        internal void InvokeViewer(string path)
+        private void SwitchPreviewRemoteInvoke(FocusedItemChangedEventArgs e)
         {
+            Debug.WriteLine("SwitchPreviewRemoteInvoke");
+
+            if (e.FocusedFile == _path)
+                return;
+
+            if (string.IsNullOrEmpty(e.FocusedFile))
+                return;
+
+            _currentMainWindow?.Dispatcher.Invoke(() =>
+            {
+                if (_currentMainWindow.Visibility != Visibility.Visible)
+                    return;
+
+                if (!WindowHelper.IsFocusedControlExplorerItem())
+                    return;
+
+                _path = NativeMethods.QuickLook.GetCurrentSelectionFirst();
+
+                InvokeViewer();
+            });
+        }
+
+        private void RunFocusMonitor()
+        {
+            if (!FocusMonitor.GetInstance().IsRunning)
+            {
+                FocusMonitor.GetInstance().Start();
+                FocusMonitor.GetInstance().FocusedItemChanged += SwitchPreviewRemoteInvoke;
+            }
+        }
+
+        private void StopFocusMonitor()
+        {
+            if (FocusMonitor.GetInstance().IsRunning)
+            {
+                FocusMonitor.GetInstance().Stop();
+                FocusMonitor.GetInstance().FocusedItemChanged -= SwitchPreviewRemoteInvoke;
+            }
+        }
+
+        internal bool InvokeViewer(string path = null)
+        {
+            if (path == null)
+                path = _path;
+
             if (string.IsNullOrEmpty(path))
-                return;
+                return false;
             if (!Directory.Exists(path) && !File.Exists(path))
-                return;
+                return false;
+
+            RunFocusMonitor();
 
             var matchedPlugin = PluginManager.GetInstance().FindMatch(path);
 
             BeginShowNewWindow(matchedPlugin, path);
+
+            return true;
         }
 
         private void BeginShowNewWindow(IViewer matchedPlugin, string path)
@@ -143,34 +207,6 @@ namespace QuickLook
             }
         }
 
-        private string GetCurrentSelection()
-        {
-            var path = string.Empty;
-
-            // communicate with COM in a separate thread
-            Task.Run(() =>
-                {
-                    var paths = GetCurrentSelectionNative();
-
-                    if (paths.Any())
-                        path = paths.First();
-                })
-                .Wait();
-
-            return string.IsNullOrEmpty(path) ? string.Empty : path;
-        }
-
-        private string[] GetCurrentSelectionNative()
-        {
-            NativeMethods.QuickLook.SaveCurrentSelection();
-
-            var n = NativeMethods.QuickLook.GetCurrentSelectionCount();
-            var sb = new StringBuilder(n * 261); // MAX_PATH + NULL = 261
-            NativeMethods.QuickLook.GetCurrentSelectionBuffer(sb);
-
-            return sb.Length == 0 ? new string[0] : sb.ToString().Split('|');
-        }
-
         internal static ViewWindowManager GetInstance()
         {
             return _instance ?? (_instance = new ViewWindowManager());