content/browser/web_contents/web_drag_dest_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 CONTENT_BROWSER_WEB_CONTENTS_WEB_DRAG_DEST_WIN_H_
   6 #define CONTENT_BROWSER_WEB_CONTENTS_WEB_DRAG_DEST_WIN_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "content/common/content_export.h"
  10 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDragOperation.h"
  11 #include "ui/base/dragdrop/drop_target.h"
  12 #include "webkit/glue/webdropdata.h"
  13
  14 namespace content {
  15 class InterstitialDropTarget;
  16 class RenderViewHost;
  17 class WebContents;
  18 class WebDragDestDelegate;
  19
  20 // A helper object that provides drop capabilities to a WebContentsImpl. The
  21 // DropTarget handles drags that enter the region of the WebContents by
  22 // passing on the events to the renderer.
  23 class CONTENT_EXPORT WebDragDest : public ui::DropTarget {
  24  public:
  25   // Create a new WebDragDest associating it with the given HWND and
  26   // WebContents.
  27   WebDragDest(HWND source_hwnd, WebContents* contents);
  28   virtual ~WebDragDest();
  29
  30   WebDropData* current_drop_data() const { return drop_data_.get(); }
  31
  32   void set_drag_cursor(WebKit::WebDragOperation op) {
  33     drag_cursor_ = op;
  34   }
  35
  36   WebDragDestDelegate* delegate() const { return delegate_; }
  37   void set_delegate(WebDragDestDelegate* d) { delegate_ = d; }
  38
  39  protected:
  40   virtual DWORD OnDragEnter(IDataObject* data_object,
  41                             DWORD key_state,
  42                             POINT cursor_position,
  43                             DWORD effect);
  44
  45   virtual DWORD OnDragOver(IDataObject* data_object,
  46                            DWORD key_state,
  47                            POINT cursor_position,
  48                            DWORD effect);
  49
  50   virtual void OnDragLeave(IDataObject* data_object);
  51
  52   virtual DWORD OnDrop(IDataObject* data_object,
  53                        DWORD key_state,
  54                        POINT cursor_position,
  55                        DWORD effect);
  56
  57  private:
  58   // Our associated WebContents.
  59   WebContents* web_contents_;
  60
  61   // We keep track of the render view host we're dragging over.  If it changes
  62   // during a drag, we need to re-send the DragEnter message.  WARNING:
  63   // this pointer should never be dereferenced.  We only use it for comparing
  64   // pointers.
  65   RenderViewHost* current_rvh_;
  66
  67   // Used to determine what cursor we should display when dragging over web
  68   // content area.  This can be updated async during a drag operation.
  69   WebKit::WebDragOperation drag_cursor_;
  70
  71   // A special drop target handler for when we try to d&d while an interstitial
  72   // page is showing.
  73   scoped_ptr<InterstitialDropTarget> interstitial_drop_target_;
  74
  75   // A delegate that can receive drag information about drag events.
  76   WebDragDestDelegate* delegate_;
  77
  78   // The data for the current drag, or NULL if |context_| is NULL.
  79   scoped_ptr<WebDropData> drop_data_;
  80
  81   DISALLOW_COPY_AND_ASSIGN(WebDragDest);
  82 };
  83
  84 }  // namespace content
  85
  86 #endif  // CONTENT_BROWSER_WEB_CONTENTS_WEB_DRAG_DEST_WIN_H_