ash/drag_drop/drag_image_view.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 "ash/drag_drop/drag_image_view.h"
   6
   7 #include "skia/ext/image_operations.h"
   8 #include "ui/aura/window.h"
   9 #include "ui/compositor/dip_util.h"
  10 #include "ui/gfx/canvas.h"
  11 #include "ui/gfx/size_conversions.h"
  12 #include "ui/views/corewm/shadow_types.h"
  13 #include "ui/views/widget/widget.h"
  14
  15 namespace ash {
  16 namespace internal {
  17
  18 namespace {
  19 using views::Widget;
  20
  21 Widget* CreateDragWidget(gfx::NativeView context) {
  22   Widget* drag_widget = new Widget;
  23   Widget::InitParams params;
  24   params.type = Widget::InitParams::TYPE_TOOLTIP;
  25   params.keep_on_top = true;
  26   params.context = context;
  27   params.accept_events = false;
  28   params.ownership = Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
  29   params.opacity = Widget::InitParams::TRANSLUCENT_WINDOW;
  30   drag_widget->Init(params);
  31   drag_widget->SetOpacity(0xFF);
  32   drag_widget->GetNativeWindow()->set_owned_by_parent(false);
  33   drag_widget->GetNativeWindow()->SetName("DragWidget");
  34   SetShadowType(drag_widget->GetNativeView(), views::corewm::SHADOW_TYPE_NONE);
  35   return drag_widget;
  36 }
  37 }
  38
  39 DragImageView::DragImageView(gfx::NativeView context) : views::ImageView() {
  40   widget_.reset(CreateDragWidget(context));
  41   widget_->SetContentsView(this);
  42   widget_->SetAlwaysOnTop(true);
  43
  44   // We are owned by the DragDropController.
  45   set_owned_by_client();
  46 }
  47
  48 DragImageView::~DragImageView() {
  49   widget_->Hide();
  50 }
  51
  52 void DragImageView::SetBoundsInScreen(const gfx::Rect& bounds) {
  53   widget_->SetBounds(bounds);
  54   widget_size_ = bounds.size();
  55 }
  56
  57 void DragImageView::SetScreenPosition(const gfx::Point& position) {
  58   widget_->SetBounds(gfx::Rect(position, widget_size_));
  59 }
  60
  61 gfx::Rect DragImageView::GetBoundsInScreen() const {
  62   return widget_->GetWindowBoundsInScreen();
  63 }
  64
  65 void DragImageView::SetWidgetVisible(bool visible) {
  66   if (visible != widget_->IsVisible()) {
  67     if (visible)
  68       widget_->Show();
  69     else
  70       widget_->Hide();
  71   }
  72 }
  73
  74 void DragImageView::SetOpacity(float visibility) {
  75   DCHECK_GE(visibility, 0.0f);
  76   DCHECK_LE(visibility, 1.0f);
  77   widget_->SetOpacity(static_cast<int>(0xff * visibility));
  78 }
  79
  80 void DragImageView::OnPaint(gfx::Canvas* canvas) {
  81   if (GetImage().isNull())
  82     return;
  83
  84   // |widget_size_| is in DIP. ImageSkia::size() also returns the size in DIP.
  85   if (GetImage().size() == widget_size_) {
  86     canvas->DrawImageInt(GetImage(), 0, 0);
  87   } else {
  88     float device_scale = 1;
  89     if (widget_->GetNativeView() && widget_->GetNativeView()->layer()) {
  90       device_scale = ui::GetDeviceScaleFactor(
  91           widget_->GetNativeView()->layer());
  92     }
  93     // The drag image already has device scale factor applied. But
  94     // |widget_size_| is in DIP units.
  95     gfx::Size scaled_widget_size = gfx::ToRoundedSize(
  96         gfx::ScaleSize(widget_size_, device_scale));
  97     gfx::ImageSkiaRep image_rep = GetImage().GetRepresentation(device_scale);
  98     if (image_rep.is_null())
  99       return;
 100     SkBitmap scaled = skia::ImageOperations::Resize(
 101         image_rep.sk_bitmap(), skia::ImageOperations::RESIZE_LANCZOS3,
 102         scaled_widget_size.width(), scaled_widget_size.height());
 103     gfx::ImageSkia image_skia(gfx::ImageSkiaRep(scaled, device_scale));
 104     canvas->DrawImageInt(image_skia, 0, 0);
 105   }
 106 }
 107
 108 }  // namespace internal
 109 }  // namespace ash