chrome/browser/ui/gtk/nine_box.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_UI_GTK_NINE_BOX_H_
   6 #define CHROME_BROWSER_UI_GTK_NINE_BOX_H_
   7
   8 #include <gtk/gtk.h>
   9
  10 namespace gfx {
  11 class Image;
  12 }
  13
  14 // A NineBox manages a set of source images representing a 3x3 grid, where
  15 // non-corner images can be tiled to make a larger image.  It's used to
  16 // use bitmaps for constructing image-based resizable widgets like buttons.
  17 //
  18 // If you want just a vertical image that stretches in height but is fixed
  19 // in width, only pass in images for the left column (leave others NULL).
  20 // Similarly, for a horizontal image that stretches in width but is fixed in
  21 // height, only pass in images for the top row.
  22 class NineBox {
  23  public:
  24   // Construct a NineBox with nine images.  Images are specified using resource
  25   // ids that will be passed to the resource bundle.  Use 0 for no image.
  26   NineBox(int top_left, int top, int top_right, int left, int center, int right,
  27           int bottom_left, int bottom, int bottom_right);
  28
  29   // Construct a NineBox from a single image and insets indicating the sizes
  30   // of the edges and corners.
  31   NineBox(int image, int top_margin, int bottom_margin, int left_margin,
  32           int right_margin);
  33   ~NineBox();
  34
  35   // Render the NineBox to |dst|.
  36   // The images will be tiled to fit into the widget.
  37   void RenderToWidget(GtkWidget* dst) const;
  38
  39   // As above, but rendered partially transparent.
  40   void RenderToWidgetWithOpacity(GtkWidget* dst, double opacity) const;
  41
  42   // Set the shape of |widget| to match that of the ninebox. Note that |widget|
  43   // must have its own window and be allocated. Also, currently only the top
  44   // three images are used.
  45   // TODO(estade): extend this function to use all 9 images (if it's ever
  46   // needed).
  47   void ContourWidget(GtkWidget* widget) const;
  48
  49  private:
  50   gfx::Image* images_[9];
  51   bool unref_images_on_destroy_;
  52 };
  53
  54 #endif  // CHROME_BROWSER_UI_GTK_NINE_BOX_H_