Implementing accelerators for Linux toolkit_views

views/focus/accelerator_handler_gtk.cc

+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <gtk/gtk.h>
+
+#include "views/focus/accelerator_handler.h"
+
+#include "views/focus/focus_manager.h"
+#include "views/widget/widget_gtk.h"
+#include "views/window/window_gtk.h"
+
+namespace views {
+
+AcceleratorHandler::AcceleratorHandler() : last_key_pressed_(0) {
+}
+
+bool AcceleratorHandler::Dispatch(GdkEvent* event) {
+  if (event->type != GDK_KEY_PRESS && event->type != GDK_KEY_RELEASE) {
+    gtk_main_do_event(event);
+    return true;
+  }
+
+  GdkEventKey* key_event = reinterpret_cast<GdkEventKey*>(event);
+  // Let's retrieve the focus manager for the GdkWindow.
+  GdkWindow* window = gdk_window_get_toplevel(key_event->window);
+  gpointer ptr;
+  gdk_window_get_user_data(window, &ptr);
+  DCHECK(ptr);  // The top-level window is expected to always be associated
+                // with the top-level gtk widget.
+  WindowGtk* widget =
+      WidgetGtk::GetWindowForNative(reinterpret_cast<GtkWidget*>(ptr));
+  FocusManager* focus_manager = widget->GetFocusManager();
+  if (!focus_manager) {
+    NOTREACHED();
+    return true;
+  }
+
+  if (event->type == GDK_KEY_PRESS) {
+    KeyEvent view_key_event(key_event, true);
+    // FocusManager::OnKeyPressed and OnKeyReleased return false if this
+    // message has been consumed and should not be propagated further.
+    if (!focus_manager->OnKeyEvent(view_key_event)) {
+      last_key_pressed_ = key_event->keyval;
+      return true;
+    }
+  }
+
+  // Key release, make sure to filter-out the key release for key press consumed
+  // as accelerators to avoid unpaired key release.
+  if (event->type == GDK_KEY_RELEASE &&
+      key_event->keyval == last_key_pressed_) {
+    last_key_pressed_ = 0;
+    return true;
+  }
+
+  gtk_main_do_event(event);
+  return true;
+}
+
+}  // namespace views