content/browser/renderer_host/gtk_key_bindings_handler.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_BROWSER_RENDERER_HOST_GTK_KEY_BINDINGS_HANDLER_H_
   6 #define CONTENT_BROWSER_RENDERER_HOST_GTK_KEY_BINDINGS_HANDLER_H_
   7
   8 #include <gtk/gtk.h>
   9
  10 #include <string>
  11
  12 #include "content/common/edit_command.h"
  13 #include "content/common/content_export.h"
  14 #include "ui/base/gtk/owned_widget_gtk.h"
  15
  16 namespace content {
  17 struct NativeWebKeyboardEvent;
  18
  19 // This class is a convenience class for handling editor key bindings defined
  20 // in gtk keyboard theme.
  21 // In gtk, only GtkEntry and GtkTextView support customizing editor key bindings
  22 // through keyboard theme. And in gtk keyboard theme definition file, each key
  23 // binding must be bound to a specific class or object. So existing keyboard
  24 // themes only define editor key bindings exactly for GtkEntry and GtkTextView.
  25 // Then, the only way for us to intercept editor key bindings defined in
  26 // keyboard theme, is to create a GtkEntry or GtkTextView object and call
  27 // gtk_bindings_activate_event() against it for the key events. If a key event
  28 // matches a predefined key binding, corresponding signal will be emitted.
  29 // GtkTextView is used here because it supports more key bindings than GtkEntry,
  30 // but in order to minimize the side effect of using a GtkTextView object, a new
  31 // class derived from GtkTextView is used, which overrides all signals related
  32 // to key bindings, to make sure GtkTextView won't receive them.
  33 //
  34 // See third_party/WebKit/Source/WebCore/editing/EditorCommand.cpp for detailed
  35 // definition of webkit edit commands.
  36 // See webkit/glue/editor_client_impl.cc for key bindings predefined in our
  37 // webkit glue.
  38 class CONTENT_EXPORT GtkKeyBindingsHandler {
  39  public:
  40   explicit GtkKeyBindingsHandler(GtkWidget* parent_widget);
  41   ~GtkKeyBindingsHandler();
  42
  43   // Matches a key event against predefined gtk key bindings, false will be
  44   // returned if the key event doesn't correspond to a predefined key binding.
  45   // Edit commands matched with |wke| will be stored in |edit_commands|.
  46   bool Match(const NativeWebKeyboardEvent& wke,
  47              EditCommands* edit_commands);
  48
  49  private:
  50   // Object structure of Handler class, which is derived from GtkTextView.
  51   struct Handler {
  52     GtkTextView parent_object;
  53     GtkKeyBindingsHandler *owner;
  54   };
  55
  56   // Class structure of Handler class.
  57   struct HandlerClass {
  58     GtkTextViewClass parent_class;
  59   };
  60
  61   // Creates a new instance of Handler class.
  62   GtkWidget* CreateNewHandler();
  63
  64   // Adds an edit command to the key event.
  65   void EditCommandMatched(const std::string& name, const std::string& value);
  66
  67   // Initializes Handler structure.
  68   static void HandlerInit(Handler *self);
  69
  70   // Initializes HandlerClass structure.
  71   static void HandlerClassInit(HandlerClass *klass);
  72
  73   // Registeres Handler class to GObject type system and return its type id.
  74   static GType HandlerGetType();
  75
  76   // Gets the GtkKeyBindingsHandler object which owns the Handler object.
  77   static GtkKeyBindingsHandler* GetHandlerOwner(GtkTextView* text_view);
  78
  79   // Handler of "backspace" signal.
  80   static void BackSpace(GtkTextView* text_view);
  81
  82   // Handler of "copy-clipboard" signal.
  83   static void CopyClipboard(GtkTextView* text_view);
  84
  85   // Handler of "cut-clipboard" signal.
  86   static void CutClipboard(GtkTextView* text_view);
  87
  88   // Handler of "delete-from-cursor" signal.
  89   static void DeleteFromCursor(GtkTextView* text_view, GtkDeleteType type,
  90                                gint count);
  91
  92   // Handler of "insert-at-cursor" signal.
  93   static void InsertAtCursor(GtkTextView* text_view, const gchar* str);
  94
  95   // Handler of "move-cursor" signal.
  96   static void MoveCursor(GtkTextView* text_view, GtkMovementStep step,
  97                          gint count, gboolean extend_selection);
  98
  99   // Handler of "move-viewport" signal.
 100   static void MoveViewport(GtkTextView* text_view, GtkScrollStep step,
 101                            gint count);
 102
 103   // Handler of "paste-clipboard" signal.
 104   static void PasteClipboard(GtkTextView* text_view);
 105
 106   // Handler of "select-all" signal.
 107   static void SelectAll(GtkTextView* text_view, gboolean select);
 108
 109   // Handler of "set-anchor" signal.
 110   static void SetAnchor(GtkTextView* text_view);
 111
 112   // Handler of "toggle-cursor-visible" signal.
 113   static void ToggleCursorVisible(GtkTextView* text_view);
 114
 115   // Handler of "toggle-overwrite" signal.
 116   static void ToggleOverwrite(GtkTextView* text_view);
 117
 118   // Handler of "show-help" signal.
 119   static gboolean ShowHelp(GtkWidget* widget, GtkWidgetHelpType arg1);
 120
 121   // Handler of "move-focus" signal.
 122   static void MoveFocus(GtkWidget* widget, GtkDirectionType arg1);
 123
 124   ui::OwnedWidgetGtk handler_;
 125
 126   // Buffer to store the match results.
 127   EditCommands edit_commands_;
 128 };
 129
 130 }  // namespace content
 131
 132 #endif  // CONTENT_BROWSER_RENDERER_HOST_GTK_KEY_BINDINGS_HANDLER_H_