GTK: Move code shared by future content/ classes and chrome/ to ui/.

BUG=93804
TEST=none


Review URL: http://codereview.chromium.org/8490029

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@111193 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 102 insertions, 0 deletions

diff --git a/ui/base/gtk/focus_store_gtk.cc b/ui/base/gtk/focus_store_gtk.cc
new file mode 100644
index 0000000..b98787c
--- /dev/null
+++ b/ui/base/gtk/focus_store_gtk.cc
@@ -0,0 +1,55 @@
+// Copyright (c) 2011 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 "ui/base/gtk/focus_store_gtk.h"
+
+#include <gtk/gtk.h>
+
+namespace ui {
+
+FocusStoreGtk::FocusStoreGtk()
+    : widget_(NULL),
+      destroy_handler_id_(0) {
+}
+
+FocusStoreGtk::~FocusStoreGtk() {
+  DisconnectDestroyHandler();
+}
+
+void FocusStoreGtk::Store(GtkWidget* widget) {
+  GtkWidget* focus_widget = NULL;
+  if (widget) {
+    // A detached widget won't have a toplevel window as an ancestor, so we
+    // can't assume that the query for toplevel will return a window.
+    GtkWidget* toplevel = gtk_widget_get_ancestor(widget, GTK_TYPE_WINDOW);
+    GtkWindow* window = GTK_IS_WINDOW(toplevel) ? GTK_WINDOW(toplevel) : NULL;
+    if (window)
+      focus_widget = window->focus_widget;
+  }
+
+  SetWidget(focus_widget);
+}
+
+void FocusStoreGtk::SetWidget(GtkWidget* widget) {
+  DisconnectDestroyHandler();
+
+  // We don't add a ref. The signal handler below effectively gives us a weak
+  // reference.
+  widget_ = widget;
+  if (widget_) {
+    // When invoked, |gtk_widget_destroyed| will set |widget_| to NULL.
+    destroy_handler_id_ = g_signal_connect(widget_, "destroy",
+                                           G_CALLBACK(gtk_widget_destroyed),
+                                           &widget_);
+  }
+}
+
+void FocusStoreGtk::DisconnectDestroyHandler() {
+  if (widget_) {
+    g_signal_handler_disconnect(widget_, destroy_handler_id_);
+    widget_ = NULL;
+  }
+}
+
+}  // namespace ui
diff --git a/ui/base/gtk/focus_store_gtk.h b/ui/base/gtk/focus_store_gtk.h
new file mode 100644
index 0000000..e237ee1
--- /dev/null
+++ b/ui/base/gtk/focus_store_gtk.h
@@ -0,0 +1,47 @@
+// Copyright (c) 2011 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.
+
+#ifndef UI_BASE_GTK_FOCUS_STORE_GTK_H_
+#define UI_BASE_GTK_FOCUS_STORE_GTK_H_
+#pragma once
+
+#include "base/basictypes.h"
+#include "ui/base/ui_export.h"
+
+typedef struct _GtkWidget GtkWidget;
+
+namespace ui {
+
+class UI_EXPORT FocusStoreGtk {
+ public:
+  FocusStoreGtk();
+  ~FocusStoreGtk();
+
+  GtkWidget* widget() const { return widget_; }
+
+  // Save the widget that is currently focused for |widget|'s toplevel (NOT
+  // |widget|).
+  void Store(GtkWidget* widget);
+
+  // Save |widget| as the focus widget. Call with NULL to clear |widget_|.
+  void SetWidget(GtkWidget* widget);
+
+ private:
+  // Disconnect the previous destroy handler (if any).
+  void DisconnectDestroyHandler();
+
+  // The widget which last had focus.
+  GtkWidget* widget_;
+
+  // The widget for which we've stored focus might be destroyed by the time we
+  // want to restore focus. Thus we connect to the "destroy" signal on that
+  // widget. This is the ID for the destroy handler.
+  unsigned int destroy_handler_id_;
+
+  DISALLOW_COPY_AND_ASSIGN(FocusStoreGtk);
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_GTK_FOCUS_STORE_GTK_H_