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/views/drag_utils.h" 6 7 #include "ui/gfx/canvas.h" 8 #include "ui/gfx/display.h" 9 #include "ui/gfx/screen.h" 10 #include "ui/gfx/size.h" 11 #include "ui/views/widget/widget.h" 12 13 namespace { 14 15 float GetDeviceScaleForNativeView(views::Widget* widget) { 16 float device_scale = 1.0f; 17 // The following code should work on other platforms as well. But we do not 18 // yet care about device scale factor on other platforms. So to keep drag and 19 // drop behavior on other platforms un-touched, we wrap this in the #if guard. 20 if (widget && widget->GetNativeView()) { 21 gfx::NativeView view = widget->GetNativeView(); 22 gfx::Display display = gfx::Screen::GetScreenFor(view)-> 23 GetDisplayNearestWindow(view); 24 device_scale = display.device_scale_factor(); 25 } 26 return device_scale; 27 } 28 29 } // namespace 30 31 namespace views { 32 33 gfx::Canvas* GetCanvasForDragImage(views::Widget* widget, 34 const gfx::Size& canvas_size) { 35 float device_scale = GetDeviceScaleForNativeView(widget); 36 return new gfx::Canvas(canvas_size, device_scale, false); 37 } 38 39 } // namespace views 40