blob: 2729151192c2d1ed9c5178dd60ff01d4f4906c05 [file] [log] [blame]
// Copyright 2017 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.
#include <memory>
#include "base/macros.h"
#include "base/time/time.h"
#include "ui/compositor/compositor_animation_observer.h"
#include "ui/compositor/layer_delegate.h"
#include "ui/gfx/geometry/rect.h"
namespace aura {
class Window;
namespace ui {
class Compositor;
class Layer;
} // namespace ui
namespace ash {
// A delegate interface implemented by the object that owns an
// AccessibilityLayer.
class AccessibilityLayerDelegate {
virtual void OnDeviceScaleFactorChanged() = 0;
virtual void OnAnimationStep(base::TimeTicks timestamp) = 0;
virtual ~AccessibilityLayerDelegate() {}
// AccessibilityLayer manages a global always-on-top layer used to
// highlight or annotate UI elements for accessibility.
class AccessibilityLayer : public ui::LayerDelegate,
public ui::CompositorAnimationObserver {
explicit AccessibilityLayer(AccessibilityLayerDelegate* delegate);
~AccessibilityLayer() override;
// Move the accessibility layer to the given bounds in the coordinates of
// the given root window.
void Set(aura::Window* root_window, const gfx::Rect& bounds);
// Set the layer's opacity.
void SetOpacity(float opacity);
// Returns true if this layer is in a composited window with an
// animation observer.
virtual bool CanAnimate() const = 0;
// Returns true if a layer needs to animate.
virtual bool NeedToAnimate() const = 0;
// Gets the inset for this layer in DIPs. This is used to increase
// the bounding box to provide space for any margins or padding.
virtual int GetInset() const = 0;
ui::Layer* layer() { return layer_.get(); }
aura::Window* root_window() { return root_window_; }
// Updates |root_window_| and creates |layer_| if it doesn't exist,
// or if the root window has changed. Moves the layer to the top if
// it wasn't there already.
void CreateOrUpdateLayer(aura::Window* root_window,
const char* layer_name,
const gfx::Rect& bounds);
// The current root window containing the focused object.
aura::Window* root_window_ = nullptr;
// The current layer.
std::unique_ptr<ui::Layer> layer_;
// The compositor associated with this layer.
ui::Compositor* compositor_ = nullptr;
// The bounding rectangle of the focused object, in |root_window_|
// coordinates.
gfx::Rect layer_rect_;
// ui::LayerDelegate overrides:
void OnDeviceScaleFactorChanged(float old_device_scale_factor,
float new_device_scale_factor) override;
// CompositorAnimationObserver overrides:
void OnAnimationStep(base::TimeTicks timestamp) override;
void OnCompositingShuttingDown(ui::Compositor* compositor) override;
// The object that owns this layer.
AccessibilityLayerDelegate* delegate_;
} // namespace ash