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_COMPOSITOR_LAYER_DELEGATE_H_ 6 #define UI_COMPOSITOR_LAYER_DELEGATE_H_ 7 8 #include "base/callback_forward.h" 9 #include "ui/compositor/compositor_export.h" 10 11 namespace gfx { 12 class Canvas; 13 } 14 15 namespace ui { 16 17 // A delegate interface implemented by an object that renders to a Layer. 18 class COMPOSITOR_EXPORT LayerDelegate { 19 public: 20 // Paint content for the layer to the specified canvas. It has already been 21 // clipped to the Layer's invalid rect. 22 virtual void OnPaintLayer(gfx::Canvas* canvas) = 0; 23 24 // Called when the layer's device scale factor has changed. 25 virtual void OnDeviceScaleFactorChanged(float device_scale_factor) = 0; 26 27 // Invoked prior to the bounds changing. The returned closured is run after 28 // the bounds change. 29 virtual base::Closure PrepareForLayerBoundsChange() = 0; 30 31 protected: 32 virtual ~LayerDelegate() {} 33 }; 34 35 } // namespace ui 36 37 #endif // UI_COMPOSITOR_LAYER_DELEGATE_H_ 38
