1// Copyright (c) 2012 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 UI_VIEWS_NATIVE_THEME_DELEGATE_H_
6#define UI_VIEWS_NATIVE_THEME_DELEGATE_H_
7
8#include "ui/gfx/rect.h"
9#include "ui/native_theme/native_theme.h"
10#include "ui/views/views_export.h"
11
12namespace views {
13
14// A delagate that supports animating transtions between different native
15// theme states.  This delegate can be used to control a native theme Border
16// or Painter object.
17//
18// If animation is ongoing, the native theme border or painter will
19// composite the foreground state over the backgroud state using an alpha
20// between 0 and 255 based on the current value of the animation.
21class VIEWS_EXPORT NativeThemeDelegate {
22 public:
23  virtual ~NativeThemeDelegate() {}
24
25  // Get the native theme part that should be drawn.
26  virtual ui::NativeTheme::Part GetThemePart() const = 0;
27
28  // Get the rectangle that should be painted.
29  virtual gfx::Rect GetThemePaintRect() const = 0;
30
31  // Get the state of the part, along with any extra data needed for drawing.
32  virtual ui::NativeTheme::State GetThemeState(
33      ui::NativeTheme::ExtraParams* params) const = 0;
34
35  // If the native theme drawign should be animated, return the Animation object
36  // that controlls it.  If no animation is ongoing, NULL may be returned.
37  virtual const gfx::Animation* GetThemeAnimation() const = 0;
38
39  // If animation is onging, this returns the background native theme state.
40  virtual ui::NativeTheme::State GetBackgroundThemeState(
41      ui::NativeTheme::ExtraParams* params) const = 0;
42
43  // If animation is onging, this returns the foreground native theme state.
44  // This state will be composited over the background using an alpha value
45  // based on the current value of the animation.
46  virtual ui::NativeTheme::State GetForegroundThemeState(
47      ui::NativeTheme::ExtraParams* params) const = 0;
48};
49
50}  // namespace views
51
52#endif  // UI_VIEWS_NATIVE_THEME_DELEGATE_H_
53