src/ui/views/widget/desktop_aura/desktop_drop_target_win.h

   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 #ifndef UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTIOP_DROP_TARGET_WIN_H_
   6 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTIOP_DROP_TARGET_WIN_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "ui/aura/window_observer.h"
  10 #include "ui/base/dragdrop/drop_target_win.h"
  11
  12 namespace aura {
  13 namespace client {
  14 class DragDropDelegate;
  15 }
  16 }
  17
  18 namespace ui {
  19 class DropTargetEvent;
  20 class OSExchangeData;
  21 }
  22
  23 namespace views {
  24
  25 // DesktopDropTargetWin takes care of managing drag and drop for
  26 // DesktopRootWindowHostWin. It converts Windows OLE drop messages into
  27 // aura::client::DragDropDelegate calls.
  28 class DesktopDropTargetWin : public ui::DropTargetWin,
  29                              public aura::WindowObserver {
  30  public:
  31   DesktopDropTargetWin(aura::Window* root_window, HWND window);
  32   virtual ~DesktopDropTargetWin();
  33
  34  private:
  35   // ui::DropTargetWin implementation:
  36   virtual DWORD OnDragEnter(IDataObject* data_object,
  37                             DWORD key_state,
  38                             POINT position,
  39                             DWORD effect) OVERRIDE;
  40   virtual DWORD OnDragOver(IDataObject* data_object,
  41                            DWORD key_state,
  42                            POINT position,
  43                            DWORD effect) OVERRIDE;
  44   virtual void OnDragLeave(IDataObject* data_object) OVERRIDE;
  45   virtual DWORD OnDrop(IDataObject* data_object,
  46                        DWORD key_state,
  47                        POINT position,
  48                        DWORD effect) OVERRIDE;
  49
  50   // aura::WindowObserver implementation:
  51   virtual void OnWindowDestroyed(aura::Window* window) OVERRIDE;
  52
  53   // Common functionality for the ui::DropTargetWin methods to translate from
  54   // COM data types to Aura ones.
  55   void Translate(IDataObject* data_object,
  56                  DWORD key_state,
  57                  POINT cursor_position,
  58                  DWORD effect,
  59                  scoped_ptr<ui::OSExchangeData>* data,
  60                  scoped_ptr<ui::DropTargetEvent>* event,
  61                  aura::client::DragDropDelegate** delegate);
  62
  63   void NotifyDragLeave();
  64
  65   // The root window associated with this drop target.
  66   aura::Window* root_window_;
  67
  68   // The Aura window that is currently under the cursor. We need to manually
  69   // keep track of this because Windows will only call our drag enter method
  70   // once when the user enters the associated HWND. But inside that HWND there
  71   // could be multiple aura windows, so we need to generate drag enter events
  72   // for them.
  73   aura::Window* target_window_;
  74
  75   DISALLOW_COPY_AND_ASSIGN(DesktopDropTargetWin);
  76 };
  77
  78 }  // namespace views
  79
  80 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTIOP_DROP_TARGET_WIN_H_