Implement GtkFloatingContainer

chrome/browser/gtk/gtk_floating_container.h

+// 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.
+
+#ifndef CHROME_BROWSER_GTK_GTK_FLOATING_CONTAINER_H_
+#define CHROME_BROWSER_GTK_GTK_FLOATING_CONTAINER_H_
+
+#include <gdk/gdk.h>
+#include <gtk/gtk.h>
+
+// A specialized container, which is a cross between a GtkBin and a
+// GtkFixed. This container dervies from GtkBin and the implementation of
+// gtk_container_add() is the same: only one GtkWidget can be added through
+// that interface. The GtkBin portion contains normal content and is given the
+// same allocation that this container has.
+//
+// In addition, any number of widgets can be through the
+// gtk_floating_container_add_floating() method, which provides functionality
+// similar to a GtkFixed. Unlike a GtkFixed, coordinates are not set when you
+// gtk_fixed_put(). The location of the floating widgets is determined while
+// running the "set-floating-position" signal, which is emitted during this
+// container's "size-allocate" handler.
+//
+// The "set-floating-position" signal is (semi-)mandatory if you want widgets
+// placed anywhere other than the origin and should have the following
+// signature:
+//
+//   void (*set_floating_position)(GtkFloatingContainer* container,
+//                                 GtkAllocation* allocation);
+//
+// Your handler should, for each floating widget, set the "x" and "y" child
+// properties.
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_FLOATING_CONTAINER                                 \
+    (gtk_floating_container_get_type())
+#define GTK_FLOATING_CONTAINER(obj)                                 \
+    (G_TYPE_CHECK_INSTANCE_CAST((obj), GTK_TYPE_FLOATING_CONTAINER, \
+                                GtkFloatingContainer))
+#define GTK_FLOATING_CONTAINER_CLASS(klass)                         \
+    (G_TYPE_CHECK_CLASS_CAST((klass), GTK_TYPE_FLOATING_CONTAINER,  \
+                             GtkFloatingContainerClass))
+#define GTK_IS_FLOATING_CONTAINER(obj)                              \
+    (G_TYPE_CHECK_INSTANCE_TYPE((obj), GTK_TYPE_FLOATING_CONTAINER))
+#define GTK_IS_FLOATING_CONTAINER_CLASS(klass)                      \
+    (G_TYPE_CHECK_CLASS_TYPE((klass), GTK_TYPE_FLOATING_CONTAINER))
+#define GTK_FLOATING_CONTAINER_GET_CLASS(obj)                       \
+    (G_TYPE_INSTANCE_GET_CLASS((obj), GTK_TYPE_FLOATING_CONTAINER,  \
+                               GtkFloatingContainerClass))
+
+typedef struct _GtkFloatingContainer GtkFloatingContainer;
+typedef struct _GtkFloatingContainerClass GtkFloatingContainerClass;
+typedef struct _GtkFloatingContainerChild GtkFloatingContainerChild;
+
+struct _GtkFloatingContainer {
+  // Parent class.
+  GtkBin bin;
+
+  // A GList of all our floating children, in GtkFloatingContainerChild
+  // structs. Owned by the GtkFloatingContainer.
+  GList* floating_children;
+};
+
+struct _GtkFloatingContainerClass {
+  GtkBinClass parent_class;
+};
+
+// Internal structure used to associate a widget and its x/y child properties.
+struct _GtkFloatingContainerChild {
+  GtkWidget* widget;
+  gint x;
+  gint y;
+};
+
+GType      gtk_floating_container_get_type() G_GNUC_CONST;
+GtkWidget* gtk_floating_container_new();
+void       gtk_floating_container_add_floating(GtkFloatingContainer* container,
+                                               GtkWidget* widget);
+// Use gtk_container_remove to remove all widgets; both widgets added with
+// gtk_container_add() and gtk_floating_container_add_floating().
+
+G_END_DECLS
+
+#endif  // CHROME_BROWSER_GTK_GTK_FLOATING_CONTAINER_H_