Add "Focusable" property to plugins

QuickLook.Plugin/QuickLook.Plugin.ArchiveViewer/Plugin.cs

@@ -30,7 +30,7 @@ namespace QuickLook.Plugin.ArchiveViewer
             return true;
         }
 
-        public void BoundViewSize(string path, ContextObject context)
+        public void Prepare(string path, ContextObject context)
         {
             context.PreferredSize = new Size {Width = 800, Height = 600};
         }

QuickLook.Plugin/QuickLook.Plugin.ImageViewer/Plugin.cs

@@ -33,7 +33,7 @@ namespace QuickLook.Plugin.ImageViewer
             }
         }
 
-        public void BoundViewSize(string path, ContextObject context)
+        public void Prepare(string path, ContextObject context)
         {
             _imageSize = ImageFileHelper.GetImageSize(path);
 

QuickLook.Plugin/QuickLook.Plugin.OfficeViewer/PluginInterface.cs

@@ -31,7 +31,7 @@ namespace QuickLook.Plugin.OfficeViewer
             return false;
         }
 
-        public void BoundViewSize(string path, ContextObject context)
+        public void Prepare(string path, ContextObject context)
         {
             context.SetPreferredSizeFit(new Size {Width = 800, Height = 600}, 0.8);
         }

QuickLook.Plugin/QuickLook.Plugin.PDFViewer/Plugin.cs

@@ -24,7 +24,7 @@ namespace QuickLook.Plugin.PDFViewer
             }
         }
 
-        public void BoundViewSize(string path, ContextObject context)
+        public void Prepare(string path, ContextObject context)
         {
             _pdfControl = new PdfViewerControl();
 

QuickLook.Plugin/QuickLook.Plugin.TextViewer/Plugin.cs

@@ -40,9 +40,10 @@ namespace QuickLook.Plugin.TextViewer
             }
         }
 
-        public void BoundViewSize(string path, ContextObject context)
+        public void Prepare(string path, ContextObject context)
         {
             context.PreferredSize = new Size {Width = 800, Height = 600};
+            context.Focusable = true;
         }
 
         public void View(string path, ContextObject context)

QuickLook/Plugin/ContextObject.cs

@@ -62,6 +62,11 @@ namespace QuickLook.Plugin
         /// </summary>
         public bool CanResize { get; set; } = true;
 
+        /// <summary>
+        ///     Set whether user are allowed to set focus at the viewer window.
+        /// </summary>
+        public bool Focusable { get; set; } = false;
+
         public void Dispose()
         {
             GC.SuppressFinalize(this);

QuickLook/Plugin/IViewer.cs

@@ -18,11 +18,11 @@
         bool CanHandle(string path);
 
         /// <summary>
-        ///     Tell QuickLook the desired window size. Please not do any work that costs a lot of time.
+        ///     Do some preparation stuff before the window is showing. Please not do any work that costs a lot of time.
         /// </summary>
         /// <param name="path">The full path of the target file.</param>
         /// <param name="context">A runtime object which allows interaction between this plugin and QuickLook.</param>
-        void BoundViewSize(string path, ContextObject context);
+        void Prepare(string path, ContextObject context);
 
         /// <summary>
         ///     Start the loading process. During the process a busy indicator will be shown. Finish by setting context.IsBusy to

QuickLook/Plugin/InfoPanel/PluginInterface.cs

@@ -14,7 +14,7 @@ namespace QuickLook.Plugin.InfoPanel
             return true;
         }
 
-        public void BoundViewSize(string path, ContextObject context)
+        public void Prepare(string path, ContextObject context)
         {
             _ip = new InfoPanel();
 

QuickLook/PluginManager.cs

@@ -33,7 +33,19 @@ namespace QuickLook
                 return null;
 
             var matched = GetInstance()
-                .LoadedPlugins.FirstOrDefault(plugin => plugin.CreateInstance<IViewer>().CanHandle(path))
+                .LoadedPlugins.FirstOrDefault(plugin =>
+                {
+                    bool can = false;
+                    try
+                    {
+                        can = plugin.CreateInstance<IViewer>().CanHandle(path);
+                    }
+                    catch (Exception)
+                    {
+                        // ignored
+                    }
+                    return can;
+                })
                 ?.CreateInstance<IViewer>();
 
             return matched ?? DefaultPlugin.CreateInstance<IViewer>();