web_drag_dest_delegate.h revision a3f6a49ab37290eeeb8db0f41ec0f1cb74a68be7 
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 CONTENT_PUBLIC_BROWSER_WEB_DRAG_DEST_DELEGATE_H_
6#define CONTENT_PUBLIC_BROWSER_WEB_DRAG_DEST_DELEGATE_H_
7
8#if defined(TOOLKIT_GTK)
9#include <gtk/gtk.h>
10#endif  // TOOLKIT_GTK
11
12#include "base/strings/string16.h"
13
14#if defined(OS_WIN)
15#include "ui/base/dragdrop/drop_target_win.h"
16#endif
17
18class GURL;
19
20namespace ui {
21class OSExchangeData;
22}
23
24namespace content {
25class WebContents;
26struct DropData;
27
28// An optional delegate that listens for drags of bookmark data.
29class WebDragDestDelegate {
30 public:
31  // Announces that a drag has started. It's valid that a drag starts, along
32  // with over/enter/leave/drop notifications without receiving any bookmark
33  // data.
34  virtual void DragInitialize(WebContents* contents) = 0;
35
36  // Notifications of drag progression.
37#if defined(OS_WIN) && !defined(USE_AURA)
38  virtual void OnDragOver(IDataObject* data_object) = 0;
39  virtual void OnDragEnter(IDataObject* data_object) = 0;
40  virtual void OnDrop(IDataObject* data_object) = 0;
41  virtual void OnDragLeave(IDataObject* data_object) = 0;
42#else
43  virtual void OnDragOver() = 0;
44  virtual void OnDragEnter() = 0;
45  virtual void OnDrop() = 0;
46  // This should also clear any state kept about this drag.
47  virtual void OnDragLeave() = 0;
48#endif
49
50#if defined(TOOLKIT_GTK)
51  // Returns the bookmark atom type. GTK and Views return different values here.
52  virtual GdkAtom GetBookmarkTargetAtom() const = 0;
53
54  // Called when WebDragDestkGtk detects that there's bookmark data in a
55  // drag. Not every drag will trigger these.
56  virtual void OnReceiveDataFromGtk(GtkSelectionData* data) = 0;
57  virtual void OnReceiveProcessedData(const GURL& url,
58                                      const base::string16& title) = 0;
59#elif defined(USE_AURA)
60  // Called at the start of every drag to supply the data associated with the
61  // drag.
62  virtual void OnReceiveDragData(const ui::OSExchangeData& data) = 0;
63#elif defined(OS_WIN)
64  // Allows the delegate to set data on the drag. If it doesn't want to set
65  // data, it should return false.
66  virtual bool AddDragData(const DropData& drop_data,
67                           ui::OSExchangeData* data) = 0;
68#endif  // TOOLKIT_GTK
69
70  virtual ~WebDragDestDelegate() {}
71};
72
73}  // namespace content
74
75#endif  // CONTENT_PUBLIC_BROWSER_WEB_DRAG_DEST_DELEGATE_H_
76