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 ASH_DRAG_DROP_DRAG_IMAGE_VIEW_H_
6#define ASH_DRAG_DROP_DRAG_IMAGE_VIEW_H_
7
8#include "ui/base/dragdrop/drag_drop_types.h"
9#include "ui/views/controls/image_view.h"
10
11namespace views {
12class Widget;
13}
14
15namespace ash {
16
17// This class allows to show a (native) view always on top of everything. It
18// does this by creating a widget and setting the content as the given view. The
19// caller can then use this object to freely move / drag it around on the
20// desktop in screen coordinates.
21class DragImageView : public views::ImageView {
22 public:
23  // |context is the native view context used to create the widget holding the
24  // drag image.
25  // |source| is the event source that started this drag drop operation (touch
26  // or mouse). It is used to determine attributes of the drag image such as
27  // whether to show drag operation hint on top of the image.
28  DragImageView(gfx::NativeView context,
29                ui::DragDropTypes::DragEventSource source);
30  virtual ~DragImageView();
31
32  // Sets the bounds of the native widget in screen
33  // coordinates.
34  // TODO(oshima): Looks like this is root window's
35  // coordinate. Change this to screen's coordinate.
36  void SetBoundsInScreen(const gfx::Rect& bounds);
37
38  // Sets the position of the native widget.
39  void SetScreenPosition(const gfx::Point& position);
40
41  // Gets the image position in screen coordinates.
42  gfx::Rect GetBoundsInScreen() const;
43
44  // Sets the visibility of the native widget.
45  void SetWidgetVisible(bool visible);
46
47  // For touch drag drop, we show a hint corresponding to the drag operation
48  // (since no mouse cursor is visible). These functions set the hint
49  // parameters.
50  void SetTouchDragOperationHintOff();
51
52  // |operation| is a bit field indicating allowable drag operations from
53  // ui::DragDropTypes::DragOperation.
54  void SetTouchDragOperation(int operation);
55  void SetTouchDragOperationHintPosition(const gfx::Point& position);
56
57  // Sets the |opacity| of the image view between 0.0 and 1.0.
58  void SetOpacity(float opacity);
59
60 private:
61  // Overridden from views::ImageView.
62  virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
63
64  scoped_ptr<views::Widget> widget_;
65  gfx::Size widget_size_;
66
67  ui::DragDropTypes::DragEventSource drag_event_source_;
68  int touch_drag_operation_;
69  gfx::Point touch_drag_operation_indicator_position_;
70
71  DISALLOW_COPY_AND_ASSIGN(DragImageView);
72};
73
74}  // namespace ash
75
76#endif  // ASH_DRAG_DROP_DRAG_IMAGE_VIEW_H_
77