tab_contents_drag_win.h revision 72a454cd3513ac24fbdd0e0cb9ad70b86a99b801 
1// Copyright (c) 2009 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 CHROME_BROWSER_UI_VIEWS_TAB_CONTENTS_TAB_CONTENTS_DRAG_WIN_H_
6#define CHROME_BROWSER_UI_VIEWS_TAB_CONTENTS_TAB_CONTENTS_DRAG_WIN_H_
7#pragma once
8
9#include "base/ref_counted.h"
10#include "base/scoped_ptr.h"
11#include "base/threading/platform_thread.h"
12#include "third_party/skia/include/core/SkBitmap.h"
13#include "third_party/WebKit/Source/WebKit/chromium/public/WebDragOperation.h"
14#include "ui/base/dragdrop/os_exchange_data_provider_win.h"
15#include "ui/gfx/point.h"
16
17class DragDropThread;
18class TabContentsViewWin;
19class WebDragSource;
20struct WebDropData;
21
22// Windows-specific drag-and-drop handling in TabContentsView.
23// If we are dragging a virtual file out of the browser, we use a background
24// thread to do the drag-and-drop because we do not want to run nested
25// message loop in the UI thread. For all other cases, the drag-and-drop happens
26// in the UI thread.
27class TabContentsDragWin
28    : public ui::DataObjectImpl::Observer,
29      public base::RefCountedThreadSafe<TabContentsDragWin> {
30 public:
31  explicit TabContentsDragWin(TabContentsViewWin* view);
32  virtual ~TabContentsDragWin();
33
34  // Called on UI thread.
35  void StartDragging(const WebDropData& drop_data,
36                     WebKit::WebDragOperationsMask ops,
37                     const SkBitmap& image,
38                     const gfx::Point& image_offset);
39  void CancelDrag();
40
41  // DataObjectImpl::Observer implementation.
42  // Called on drag-and-drop thread.
43  virtual void OnWaitForData();
44  virtual void OnDataObjectDisposed();
45
46 private:
47  // Called on either UI thread or drag-and-drop thread.
48  void PrepareDragForDownload(const WebDropData& drop_data,
49                              ui::OSExchangeData* data,
50                              const GURL& page_url,
51                              const std::string& page_encoding);
52  void PrepareDragForFileContents(const WebDropData& drop_data,
53                                  ui::OSExchangeData* data);
54  void PrepareDragForUrl(const WebDropData& drop_data,
55                         ui::OSExchangeData* data);
56  void DoDragging(const WebDropData& drop_data,
57                  WebKit::WebDragOperationsMask ops,
58                  const GURL& page_url,
59                  const std::string& page_encoding,
60                  const SkBitmap& image,
61                  const gfx::Point& image_offset);
62
63  // Called on drag-and-drop thread.
64  void StartBackgroundDragging(const WebDropData& drop_data,
65                               WebKit::WebDragOperationsMask ops,
66                               const GURL& page_url,
67                               const std::string& page_encoding,
68                               const SkBitmap& image,
69                               const gfx::Point& image_offset);
70  // Called on UI thread.
71  void EndDragging(bool restore_suspended_state);
72  void CloseThread();
73
74  // For debug check only. Access only on drag-and-drop thread.
75  base::PlatformThreadId drag_drop_thread_id_;
76
77  // All the member variables below are accessed on UI thread.
78
79  // Keep track of the TabContentsViewWin it is associated with.
80  TabContentsViewWin* view_;
81
82  // |drag_source_| is our callback interface passed to the system when we
83  // want to initiate a drag and drop operation.  We use it to tell if a
84  // drag operation is happening.
85  scoped_refptr<WebDragSource> drag_source_;
86
87  // The thread used by the drag-out download. This is because we want to avoid
88  // running nested message loop in main UI thread.
89  scoped_ptr<DragDropThread> drag_drop_thread_;
90
91  // The flag to guard that EndDragging is not called twice.
92  bool drag_ended_;
93
94  // Keep track of the old suspended state of the drop target.
95  bool old_drop_target_suspended_state_;
96
97  DISALLOW_COPY_AND_ASSIGN(TabContentsDragWin);
98};
99
100
101#endif  // CHROME_BROWSER_UI_VIEWS_TAB_CONTENTS_TAB_CONTENTS_DRAG_WIN_H_
102