do not show preview window on every SPACE key; code refactoring

QuickLook.Native.Shell32/QuickLook.Native.Shell32.cpp

@@ -5,6 +5,11 @@
 
 #define EXPORT extern "C" __declspec(dllexport)
 
+EXPORT int GetFocusedWindowType()
+{
+	return Shell32::GetFocusedWindowType();
+}
+
 EXPORT void SaveCurrentSelection()
 {
 	Shell32::SaveCurrentSelection();

QuickLook.Native.Shell32/Shell32.h

@@ -5,24 +5,23 @@
 class Shell32
 {
 public:
+	enum FocusedWindowType
+	{
+		INVALID = 0,
+		DESKTOP = 1,
+		EXPLORER = 2,
+	};
+	static FocusedWindowType GetFocusedWindowType();
 	static void SaveCurrentSelection();
 	static UINT GetCurrentSelectionCount();
 	static void GetCurrentSelectionBuffer(PWCHAR buffer);
 
 private:
-	enum FocusedWindowType
-	{
-		INVALID,
-		DESKTOP,
-		EXPLORER,
-	};
-
 	static std::vector<std::wstring> vector_items;
 
 	static void SaveSelectedFromDesktop();
 	static void SaveSelectedFromExplorer();
 
-	static FocusedWindowType GetFocusedWindowType();
 	static CComQIPtr<IWebBrowser2> AttachDesktopShellWindow();
 	static void vectorFromDataObject(CComPtr<IDataObject> dao);
 };

QuickLook.Plugin.LastResort/IconHelper.cs

@@ -7,7 +7,7 @@ using System.Runtime.InteropServices;
 
 namespace QuickLook.Plugin.LastResort
 {
-    public class IconHelper
+    public static class IconHelper
     {
         public enum IconSizeEnum
         {

QuickLook/BackgroundListener.cs

@@ -1,8 +1,4 @@
-using System;
+using System.Windows.Forms;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-using System.Windows.Forms;
 using QuickLook.Utilities;
 
 namespace QuickLook
@@ -13,8 +9,6 @@ namespace QuickLook
 
         private GlobalKeyboardHook _hook;
 
-        private MainWindow _showingWindow;
-
         protected BackgroundListener()
         {
             InstallHook(HotkeyEventHandler);
@@ -22,49 +16,7 @@ namespace QuickLook
 
         private void HotkeyEventHandler(object sender, KeyEventArgs e)
         {
-            if (_showingWindow != null)
+            ViewWindowManager.GetInstance().InvokeRoutine();
-            {
-                _showingWindow.Close();
-                _showingWindow = null;
-
-                GC.Collect();
-
-                return;
-            }
-
-            var path = string.Empty;
-
-            // communicate with COM in a separate thread
-            Task.Run(() =>
-                {
-                    var paths = GetCurrentSelection();
-
-                    if (paths.Any())
-                        path = paths.First();
-                })
-                .Wait();
-
-            if (string.IsNullOrEmpty(path))
-                return;
-
-            var matched = PluginManager.FindMatch(path);
-
-            if (matched == null)
-                return;
-
-            _showingWindow = new MainWindow();
-            _showingWindow.Closed += (sender2, e2) => { _showingWindow = null; };
-
-            _showingWindow.viewContentContainer.ViewerPlugin = matched;
-
-            // get window size before showing it
-            matched.Prepare(path, _showingWindow.viewContentContainer);
-
-            _showingWindow.Show();
-
-            matched.View(path, _showingWindow.viewContentContainer);
-
-            _showingWindow.ShowFinishLoadingAnimation();
         }
 
         private void InstallHook(KeyEventHandler handler)
@@ -76,19 +28,6 @@ namespace QuickLook
             _hook.KeyUp += handler;
         }
 
-        private string[] GetCurrentSelection()
-        {
-            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 BackgroundListener GetInstance()
         {
             return _instance ?? (_instance = new BackgroundListener());

QuickLook/MainWindow.xaml.cs

@@ -8,6 +8,7 @@ using System.Windows.Media.Animation;
 using System.Windows.Threading;
 using QuickLook.Annotations;
 using QuickLook.ExtensionMethods;
+using QuickLook.Plugin;
 using QuickLook.Utilities;
 
 namespace QuickLook
@@ -53,10 +54,24 @@ namespace QuickLook
 
             base.Show();
 
-            NoactivateWindowHelper.SetNoactivate(new WindowInteropHelper(this));
+            WindowHelper.SetNoactivate(new WindowInteropHelper(this));
         }
 
-        internal void ShowFinishLoadingAnimation()
+        internal void BeginShow(IViewer matchedPlugin, string path)
+        {
+            viewContentContainer.ViewerPlugin = matchedPlugin;
+
+            // get window size before showing it
+            matchedPlugin.Prepare(path, viewContentContainer);
+
+            Show();
+
+            matchedPlugin.View(path, viewContentContainer);
+
+            ShowFinishLoadingAnimation();
+        }
+
+        private void ShowFinishLoadingAnimation()
         {
             var speed = 100;
 

QuickLook/NativeMethods/Kernel32.cs

@@ -3,9 +3,12 @@ using System.Runtime.InteropServices;
 
 namespace QuickLook.NativeMethods
 {
-    internal class Kernel32
+    internal static class Kernel32
     {
         [DllImport("kernel32.dll")]
         internal static extern IntPtr LoadLibrary(string lpFileName);
+
+        [DllImport("kernel32.dll")]
+        internal static extern IntPtr GetCurrentThreadId();
     }
 }

QuickLook/NativeMethods/QuickLook.cs

@@ -3,8 +3,11 @@ using System.Text;
 
 namespace QuickLook.NativeMethods
 {
-    internal class QuickLook
+    internal static class QuickLook
     {
+        [DllImport("QuickLook.Native.Shell32.dll", CallingConvention = CallingConvention.Cdecl)]
+        internal static extern int GetFocusedWindowType();
+
         [DllImport("QuickLook.Native.Shell32.dll", CallingConvention = CallingConvention.Cdecl)]
         internal static extern void SaveCurrentSelection();
 

QuickLook/NativeMethods/User32.cs

@@ -1,10 +1,11 @@
 using System;
 using System.Diagnostics.CodeAnalysis;
 using System.Runtime.InteropServices;
+using System.Text;
 
 namespace QuickLook.NativeMethods
 {
-    internal class User32
+    internal static class User32
     {
         [DllImport("user32.dll")]
         internal static extern IntPtr SetWindowsHookEx(int idHook, KeyboardHookProc callback, IntPtr hInstance,
@@ -17,10 +18,28 @@ namespace QuickLook.NativeMethods
         internal static extern int CallNextHookEx(IntPtr idHook, int nCode, int wParam, ref KeyboardHookStruct lParam);
 
         [DllImport("user32.dll")]
-        public static extern IntPtr SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
+        internal static extern IntPtr SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
 
         [DllImport("user32.dll")]
-        public static extern int GetWindowLong(IntPtr hWnd, int nIndex);
+        internal static extern int GetWindowLong(IntPtr hWnd, int nIndex);
+
+        [DllImport("user32.dll")]
+        internal static extern IntPtr GetForegroundWindow();
+
+        [DllImport("user32.dll")]
+        internal static extern IntPtr GetWindowThreadProcessId(IntPtr hWnd, IntPtr ProcessId);
+
+        [DllImport("user32.dll")]
+        internal static extern IntPtr AttachThreadInput(IntPtr idAttach, IntPtr idAttachTo, bool fAttach);
+
+        [DllImport("user32.dll")]
+        internal static extern IntPtr GetFocus();
+
+        [DllImport("user32.dll", CharSet = CharSet.Auto)]
+        internal static extern int GetClassName(IntPtr hWnd, StringBuilder lpClassName, int nMaxCount);
+
+        [DllImport("user32.dll")]
+        internal static extern IntPtr GetParent(IntPtr hWnd);
 
         internal delegate int KeyboardHookProc(int code, int wParam, ref KeyboardHookStruct lParam);
 

QuickLook/QuickLook.csproj

@@ -79,7 +79,8 @@
     <Compile Include="Plugin\ViewContentContainer.xaml.cs">
       <DependentUpon>ViewContentContainer.xaml</DependentUpon>
     </Compile>
-    <Compile Include="Utilities\NoactivateWindowHelper.cs" />
+    <Compile Include="Utilities\WindowHelper.cs" />
+    <Compile Include="ViewWindowManager.cs" />
     <Page Include="Styles\ScrollBarStyleDictionary.xaml">
       <SubType>Designer</SubType>
       <Generator>MSBuild:Compile</Generator>

QuickLook/Utilities/AeroGlass.cs

@@ -5,7 +5,7 @@ using System.Windows.Interop;
 
 namespace QuickLook.Utilities
 {
-    internal class AeroGlass
+    internal static class AeroGlass
     {
         internal static void EnableBlur(Window window)
         {

QuickLook/Utilities/NoactivateWindowHelper.cs

@@ -1,15 +0,0 @@
-using System.Windows.Interop;
-using QuickLook.NativeMethods;
-
-namespace QuickLook.Utilities
-{
-    internal class NoactivateWindowHelper
-    {
-        internal static void SetNoactivate(WindowInteropHelper window)
-        {
-            User32.SetWindowLong(window.Handle, User32.GWL_EXSTYLE,
-                User32.GetWindowLong(window.Handle, User32.GWL_EXSTYLE) |
-                User32.WS_EX_NOACTIVATE);
-        }
-    }
-}

QuickLook/Utilities/WindowHelper.cs

@@ -0,0 +1,62 @@
+using System;
+using System.Text;
+using System.Windows.Interop;
+using QuickLook.NativeMethods;
+
+namespace QuickLook.Utilities
+{
+    internal static class WindowHelper
+    {
+        internal static void SetNoactivate(WindowInteropHelper window)
+        {
+            User32.SetWindowLong(window.Handle, User32.GWL_EXSTYLE,
+                User32.GetWindowLong(window.Handle, User32.GWL_EXSTYLE) |
+                User32.WS_EX_NOACTIVATE);
+        }
+
+        internal static string GetWindowClassName(IntPtr window)
+        {
+            var pClassName = new StringBuilder(256);
+            User32.GetClassName(window, pClassName, pClassName.Capacity);
+
+            return pClassName.ToString();
+        }
+
+        internal static IntPtr GetParentWindow(IntPtr child)
+        {
+            return User32.GetParent(child);
+        }
+
+        internal static IntPtr GetFocusedWindow()
+        {
+            var activeWindowHandle = User32.GetForegroundWindow();
+
+            var activeWindowThread = User32.GetWindowThreadProcessId(activeWindowHandle, IntPtr.Zero);
+            var currentThread = Kernel32.GetCurrentThreadId();
+
+            User32.AttachThreadInput(activeWindowThread, currentThread, true);
+            var focusedControlHandle = User32.GetFocus();
+            User32.AttachThreadInput(activeWindowThread, currentThread, false);
+
+            return focusedControlHandle;
+        }
+
+        internal static bool IsFocusedControlExplorerItem()
+        {
+            if (NativeMethods.QuickLook.GetFocusedWindowType() == 0)
+                return false;
+
+            var focusedWindowClass = GetWindowClassName(GetFocusedWindow());
+            var focusedWindowParentClass =
+                GetWindowClassName(GetParentWindow(GetFocusedWindow()));
+
+            if (focusedWindowParentClass != "SHELLDLL_DefView")
+                return false;
+
+            if (focusedWindowClass != "SysListView32" && focusedWindowClass != "DirectUIHWND")
+                return false;
+
+            return true;
+        }
+    }
+}

QuickLook/ViewWindowManager.cs

@@ -0,0 +1,90 @@
+using System;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using QuickLook.Plugin;
+using QuickLook.Utilities;
+
+namespace QuickLook
+{
+    internal class ViewWindowManager
+    {
+        private static ViewWindowManager _instance;
+
+        private MainWindow _viewWindow;
+
+        internal void InvokeRoutine()
+        {
+            if (CloseCurrentWindow())
+                return;
+
+            if (!WindowHelper.IsFocusedControlExplorerItem())
+                return;
+
+            var path = GetCurrentSelection();
+            if (string.IsNullOrEmpty(path))
+                return;
+
+            var matchedPlugin = PluginManager.FindMatch(path);
+            if (matchedPlugin == null)
+                return;
+
+            BeginShowNewWindow(matchedPlugin, path);
+        }
+
+        private void BeginShowNewWindow(IViewer matchedPlugin, string path)
+        {
+            _viewWindow = new MainWindow();
+            _viewWindow.Closed += (sender2, e2) => { _viewWindow = null; };
+
+            _viewWindow.BeginShow(matchedPlugin, path);
+        }
+
+        private bool CloseCurrentWindow()
+        {
+            if (_viewWindow != null)
+            {
+                _viewWindow.Close();
+                _viewWindow = null;
+
+                GC.Collect();
+
+                return true;
+            }
+            return false;
+        }
+
+        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());
+        }
+    }
+}