Revert "Fix #644: still use focusable window on Windows 7 and 8"

This reverts commit 452574e.

Revert "Fix #644 step 1: correctly bring window back to top when clicked"

This reverts commit af608dc.

Author: xupefei

QuickLook/ViewerWindow.xaml.cs

@@ -18,13 +18,14 @@
 using System;
 using System.Windows;
 using System.Windows.Input;
-using System.Windows.Interop;
-using System.Windows.Media;
 using System.Windows.Media.Animation;
 using QuickLook.Common.ExtensionMethods;
 using QuickLook.Common.Helpers;
 using QuickLook.Common.Plugin;
 using QuickLook.Helpers;
+using Brush = System.Windows.Media.Brush;
+using FontFamily = System.Windows.Media.FontFamily;
+using Size = System.Windows.Size;
 
 namespace QuickLook
 {
@@ -54,14 +55,8 @@ internal ViewerWindow()
 
             StateChanged += (sender, e) => _ignoreNextWindowSizeChange = true;
 
-            // bring the window to top when users click in the client area.
-            // the non-client area is handled by the WndProc inside OnSourceInitialized().
-            // This is buggy for Windows 7 and 8: https://github.com/QL-Win/QuickLook/issues/644#issuecomment-628921704
-            if (App.IsWin10)
-                PreviewMouseDown += (sender, e) => this.BringToFront(false);
-
             windowFrameContainer.PreviewMouseMove += ShowWindowCaptionContainer;
-
+            
             Topmost = SettingHelper.Get("Topmost", false);
             buttonTop.Tag = Topmost ? "Top" : "Auto";
 
@@ -103,32 +98,6 @@ internal ViewerWindow()
             buttonOpenWith.Click += (sender, e) => ShareHelper.Share(_path, this, true);
         }
 
-        // bring the window to top when users click in the non-client area.
-        protected override void OnSourceInitialized(EventArgs e)
-        {
-            base.OnSourceInitialized(e);
-
-            // The non-focusable trick is buggy for Windows 7 and 8
-            // https://github.com/QL-Win/QuickLook/issues/644#issuecomment-628921704
-            if (App.IsWin10)
-            {
-                this.SetNoactivate();
-
-                HwndSource.FromHwnd(new WindowInteropHelper(this).Handle)?.AddHook(
-                    (IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled) =>
-                    {
-                        switch (msg)
-                        {
-                            case 0x0112: // WM_SYSCOMMAND
-                                this.BringToFront(false);
-                                break;
-                        }
-
-                        return IntPtr.Zero;
-                    });
-            }
-        }
-
         public override void OnApplyTemplate()
         {
             base.OnApplyTemplate();