Resize synchronization for Linux.

gfx/gtk_preserve_window.cc

 // Copyright (c) 2010 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 "gfx/gtk_preserve_window.h"
 
 #include <gdk/gdkwindow.h>
 #include <gtk/gtk.h>
 #include <gtk/gtkwidget.h>
 #include <gtk/gtkfixed.h>
 
 G_BEGIN_DECLS
 
 #define GTK_PRESERVE_WINDOW_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), \
                                             GTK_TYPE_PRESERVE_WINDOW, \
                                             GtkPreserveWindowPrivate))
 
 typedef struct _GtkPreserveWindowPrivate GtkPreserveWindowPrivate;
 
 struct _GtkPreserveWindowPrivate {
   // If true, don't create/destroy windows on realize/unrealize.
   gboolean preserve_window;
+
+  // Whether or not we delegate the resize of the GdkWindow
+  // to someone else.
+  gboolean delegate_resize;
 };
 
 G_DEFINE_TYPE(GtkPreserveWindow, gtk_preserve_window, GTK_TYPE_FIXED)
 
 static void gtk_preserve_window_destroy(GtkObject* object);
 static void gtk_preserve_window_realize(GtkWidget* widget);
 static void gtk_preserve_window_unrealize(GtkWidget* widget);
+static void gtk_preserve_window_size_allocate(GtkWidget* widget,
+                                              GtkAllocation* allocation);
 
 static void gtk_preserve_window_class_init(GtkPreserveWindowClass *klass) {
   GtkWidgetClass* widget_class = reinterpret_cast<GtkWidgetClass*>(klass);
   widget_class->realize = gtk_preserve_window_realize;
   widget_class->unrealize = gtk_preserve_window_unrealize;
+  widget_class->size_allocate = gtk_preserve_window_size_allocate;
 
   GtkObjectClass* object_class = reinterpret_cast<GtkObjectClass*>(klass);
   object_class->destroy = gtk_preserve_window_destroy;
 
   GObjectClass* gobject_class = G_OBJECT_CLASS(klass);
   g_type_class_add_private(gobject_class, sizeof(GtkPreserveWindowPrivate));
 }
 
 static void gtk_preserve_window_init(GtkPreserveWindow* widget) {
   GtkPreserveWindowPrivate* priv = GTK_PRESERVE_WINDOW_GET_PRIVATE(widget);
@@ skipping 21 matching lines @@
 
 static void gtk_preserve_window_realize(GtkWidget* widget) {
   g_return_if_fail(GTK_IS_PRESERVE_WINDOW(widget));
 
   if (widget->window) {
     gdk_window_reparent(widget->window,
                         gtk_widget_get_parent_window(widget),
                         widget->allocation.x,
                         widget->allocation.y);
     widget->style = gtk_style_attach(widget->style, widget->window);
+    gtk_style_set_background(widget->style, widget->window, GTK_STATE_NORMAL);
+
+    gint event_mask = gtk_widget_get_events(widget);
+    event_mask |= GDK_EXPOSURE_MASK | GDK_BUTTON_PRESS_MASK;
+    gdk_window_set_events(widget->window, (GdkEventMask) event_mask);
     gdk_window_set_user_data(widget->window, widget);
 
     // Deprecated as of GTK 2.22. Used for compatibility.
     // It should be: gtk_widget_set_realized(widget, TRUE)
     GTK_WIDGET_SET_FLAGS(widget, GTK_REALIZED);
   } else {
     GTK_WIDGET_CLASS(gtk_preserve_window_parent_class)->realize(widget);
   }
 }
 
@@ skipping 59 matching lines @@
     // that a size-allocation will resize it later.
     attributes.width = 1;
     attributes.height = 1;
 
     attributes.window_type = GDK_WINDOW_CHILD;
     attributes.wclass = GDK_INPUT_OUTPUT;
 
     attributes.visual = gtk_widget_get_visual(widget);
     attributes.colormap = gtk_widget_get_colormap(widget);
 
-    attributes.event_mask = gtk_widget_get_events(widget);
-    attributes.event_mask |= GDK_EXPOSURE_MASK | GDK_BUTTON_PRESS_MASK;
-
     attributes_mask = GDK_WA_VISUAL | GDK_WA_COLORMAP;
     widget->window = gdk_window_new(
         gdk_get_default_root_window(), &attributes, attributes_mask);
   }
 }
 
+void gtk_preserve_window_size_allocate(GtkWidget* widget,
+                                       GtkAllocation* allocation) {
+  g_return_if_fail(GTK_IS_PRESERVE_WINDOW(widget));
+  GtkPreserveWindowPrivate* priv = GTK_PRESERVE_WINDOW_GET_PRIVATE(widget);
+
+  if (priv->delegate_resize) {
+    // Just update the state. Someone else will gdk_window_resize the
+    // associated GdkWindow.
+    widget->allocation = *allocation;
+  } else {
+    GTK_WIDGET_CLASS(gtk_preserve_window_parent_class)->size_allocate(
+        widget, allocation);
+  }
+}
+
+void gtk_preserve_window_delegate_resize(GtkPreserveWindow* widget,
+                                         gboolean delegate) {
+  GtkPreserveWindowPrivate* priv = GTK_PRESERVE_WINDOW_GET_PRIVATE(widget);
+  priv->delegate_resize = delegate;
+}
+
 G_END_DECLS