Implements WidgetGtk::SetOpacity.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/164346

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@23169 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 13 insertions, 3 deletions

diff --git a/views/widget/widget_gtk.cc b/views/widget/widget_gtk.cc
index 8a65022..6534cca 100644
--- a/views/widget/widget_gtk.cc
+++ b/views/widget/widget_gtk.cc
@@ -68,7 +68,8 @@ WidgetGtk::WidgetGtk(Type type)
       last_mouse_event_was_move_(false),
       ALLOW_THIS_IN_INITIALIZER_LIST(close_widget_factory_(this)),
       delete_on_destroy_(true),
-      transparent_(false) {
+      transparent_(false),
+      opacity_(255) {
   if (type_ != TYPE_CHILD)
     focus_manager_.reset(new FocusManager(this));
 }
@@ -136,6 +137,9 @@ void WidgetGtk::Init(GtkWidget* parent,
   // Make container here.
   CreateGtkWidget(parent, bounds);
 
+  if (opacity_ != 255)
+    SetOpacity(opacity_);
+
   // Make sure we receive our motion events.
 
   // In general we register most events on the parent of all widgets. At a
@@ -317,8 +321,12 @@ void WidgetGtk::PaintNow(const gfx::Rect& update_rect) {
 }
 
 void WidgetGtk::SetOpacity(unsigned char opacity) {
-  // TODO(port): implement this feature.
-  NOTIMPLEMENTED();
+  opacity_ = opacity;
+  if (widget_) {
+    // We can only set the opacity when the widget has been realized.
+    gdk_window_set_opacity(widget_->window, static_cast<gdouble>(opacity) /
+                           static_cast<gdouble>(255));
+  }
 }
 
 RootView* WidgetGtk::GetRootView() {
diff --git a/views/widget/widget_gtk.h b/views/widget/widget_gtk.h
index b3308c4..f8c6a20 100644
--- a/views/widget/widget_gtk.h
+++ b/views/widget/widget_gtk.h
@@ -253,6 +253,8 @@ class WidgetGtk : public Widget, public MessageLoopForUI::Observer {
 
   scoped_ptr<DefaultThemeProvider> default_theme_provider_;
 
+  unsigned char opacity_;
+
   DISALLOW_COPY_AND_ASSIGN(WidgetGtk);
 };