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// Copyright 2013 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 UI_GFX_SCOPED_CANVAS_H_
#define UI_GFX_SCOPED_CANVAS_H_

#include "ui/gfx/canvas.h"

namespace gfx {

// Saves the drawing state, and restores the state when going out of scope.
class ScopedCanvas {
 public:
  explicit ScopedCanvas(gfx::Canvas* canvas) : canvas_(canvas) {
    if (canvas_)
      canvas_->Save();
  }
  ~ScopedCanvas() {
    if (canvas_)
      canvas_->Restore();
  }
  void SetCanvas(gfx::Canvas* canvas) {
    if (canvas_)
      canvas_->Restore();
    canvas_ = canvas;
    canvas_->Save();
  }

 private:
  gfx::Canvas* canvas_;

  DISALLOW_COPY_AND_ASSIGN(ScopedCanvas);
};

}  // namespace gfx

#endif  // UI_GFX_SCOPED_CANVAS_H_