ui/views/drag_utils.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/views/drag_utils.h"
   6
   7 #include "ui/gfx/canvas.h"
   8 #include "ui/gfx/size.h"
   9
  10 #if defined(USE_AURA)
  11 #include "ui/aura/client/drag_drop_client.h"
  12 #include "ui/aura/root_window.h"
  13 #include "ui/aura/window.h"
  14 #include "ui/gfx/display.h"
  15 #include "ui/gfx/screen.h"
  16 #include "ui/views/widget/widget.h"
  17 #elif defined(OS_WIN)
  18 #include "ui/base/dragdrop/drag_drop_types.h"
  19 #include "ui/base/dragdrop/drag_source.h"
  20 #include "ui/base/dragdrop/os_exchange_data_provider_win.h"
  21 #else
  22 #error
  23 #endif
  24
  25 ui::ScaleFactor GetDeviceScaleFactorForNativeView(views::Widget* widget) {
  26   ui::ScaleFactor device_scale_factor = ui::SCALE_FACTOR_100P;
  27 #if defined(USE_AURA)
  28   // The following code should work on other platforms as well. But we do not
  29   // yet care about device scale factor on other platforms. So to keep drag and
  30   // drop behavior on other platforms un-touched, we wrap this in the #if guard.
  31   if (widget && widget->GetNativeView()) {
  32     gfx::NativeView view = widget->GetNativeView();
  33     gfx::Display display = gfx::Screen::GetScreenFor(view)->
  34         GetDisplayNearestWindow(view);
  35     device_scale_factor = ui::GetScaleFactorFromScale(
  36         display.device_scale_factor());
  37   }
  38 #endif
  39   return device_scale_factor;
  40 }
  41
  42 namespace views {
  43
  44 void RunShellDrag(gfx::NativeView view,
  45                   const ui::OSExchangeData& data,
  46                   const gfx::Point& location,
  47                   int operation,
  48                   ui::DragDropTypes::DragEventSource source) {
  49 #if defined(USE_AURA)
  50   gfx::Point root_location(location);
  51   aura::RootWindow* root_window = view->GetRootWindow();
  52   aura::Window::ConvertPointToTarget(view, root_window, &root_location);
  53   if (aura::client::GetDragDropClient(root_window)) {
  54     aura::client::GetDragDropClient(root_window)->StartDragAndDrop(
  55         data, root_window, view, root_location, operation, source);
  56   }
  57 #elif defined(OS_WIN)
  58   scoped_refptr<ui::DragSource> drag_source(new ui::DragSource);
  59   DWORD effects;
  60   DoDragDrop(ui::OSExchangeDataProviderWin::GetIDataObject(data),
  61              drag_source,
  62              ui::DragDropTypes::DragOperationToDropEffect(operation),
  63              &effects);
  64 #endif
  65 }
  66
  67 gfx::Canvas* GetCanvasForDragImage(views::Widget* widget,
  68                                    const gfx::Size& canvas_size) {
  69   ui::ScaleFactor device_scale_factor =
  70       GetDeviceScaleFactorForNativeView(widget);
  71   return new gfx::Canvas(canvas_size, device_scale_factor, false);
  72 }
  73
  74 }  // namespace views