ui/compositor/layer_owner.cc

   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 #include "ui/compositor/layer_owner.h"
   6
   7 #include "ui/compositor/layer_owner_delegate.h"
   8
   9 namespace ui {
  10
  11 LayerOwner::LayerOwner() : layer_(NULL), layer_owner_delegate_(NULL) {
  12 }
  13
  14 LayerOwner::~LayerOwner() {
  15 }
  16
  17 void LayerOwner::SetLayer(Layer* layer) {
  18   DCHECK(!OwnsLayer());
  19   layer_owner_.reset(layer);
  20   layer_ = layer;
  21   layer_->owner_ = this;
  22 }
  23
  24 scoped_ptr<Layer> LayerOwner::AcquireLayer() {
  25   if (layer_owner_)
  26     layer_owner_->owner_ = NULL;
  27   return layer_owner_.Pass();
  28 }
  29
  30 scoped_ptr<Layer> LayerOwner::RecreateLayer() {
  31   scoped_ptr<ui::Layer> old_layer(AcquireLayer());
  32   if (!old_layer)
  33     return old_layer.Pass();
  34
  35   LayerDelegate* old_delegate = old_layer->delegate();
  36   old_layer->set_delegate(NULL);
  37
  38   const gfx::Rect layer_bounds(old_layer->bounds());
  39   Layer* new_layer = new ui::Layer(old_layer->type());
  40   SetLayer(new_layer);
  41   new_layer->SetVisible(old_layer->GetTargetVisibility());
  42   new_layer->SetOpacity(old_layer->GetTargetOpacity());
  43   new_layer->SetBounds(layer_bounds);
  44   new_layer->SetMasksToBounds(old_layer->GetMasksToBounds());
  45   new_layer->set_name(old_layer->name());
  46   new_layer->SetFillsBoundsOpaquely(old_layer->fills_bounds_opaquely());
  47   new_layer->SetFillsBoundsCompletely(old_layer->FillsBoundsCompletely());
  48   new_layer->SetSubpixelPositionOffset(old_layer->subpixel_position_offset());
  49   if (old_layer->type() == LAYER_SOLID_COLOR)
  50     new_layer->SetColor(old_layer->GetTargetColor());
  51   SkRegion* alpha_shape = old_layer->alpha_shape();
  52   if (alpha_shape)
  53     new_layer->SetAlphaShape(make_scoped_ptr(new SkRegion(*alpha_shape)));
  54
  55   // Install new layer as a sibling of the old layer, stacked below it.
  56   if (old_layer->parent()) {
  57     old_layer->parent()->Add(new_layer);
  58     old_layer->parent()->StackBelow(new_layer, old_layer.get());
  59   }
  60
  61   // Migrate all the child layers over to the new layer. Copy the list because
  62   // the items are removed during iteration.
  63   std::vector<ui::Layer*> children_copy = old_layer->children();
  64   for (std::vector<ui::Layer*>::const_iterator it = children_copy.begin();
  65        it != children_copy.end();
  66        ++it) {
  67     ui::Layer* child = *it;
  68     new_layer->Add(child);
  69   }
  70
  71   // If old_layer was the layer tree root then we need to move the Compositor
  72   // over to the new root.
  73   const bool is_root = !old_layer->parent();
  74   if (is_root && old_layer->GetCompositor())
  75     old_layer->GetCompositor()->SetRootLayer(new_layer);
  76
  77   // Install the delegate last so that the delegate isn't notified as we copy
  78   // state to the new layer.
  79   new_layer->set_delegate(old_delegate);
  80
  81   if (layer_owner_delegate_)
  82     layer_owner_delegate_->OnLayerRecreated(old_layer.get(), new_layer);
  83
  84   return old_layer.Pass();
  85 }
  86
  87 void LayerOwner::DestroyLayer() {
  88   layer_ = NULL;
  89   layer_owner_.reset();
  90 }
  91
  92 bool LayerOwner::OwnsLayer() const {
  93   return !!layer_owner_;
  94 }
  95
  96 }  // namespace ui