gecko-dev/dom/base/nsContentAreaDragDrop.h

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2.6 KiB
C++

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef nsContentAreaDragDrop_h__
#define nsContentAreaDragDrop_h__
#include "nsCOMPtr.h"
#include "nsIDOMEventListener.h"
#include "nsITransferable.h"
class nsPIDOMWindow;
class nsISelection;
class nsITransferable;
class nsIContent;
class nsIFile;
namespace mozilla {
namespace dom {
class DataTransfer;
}
}
//
// class nsContentAreaDragDrop, used to generate the dragdata
//
class nsContentAreaDragDrop
{
public:
/**
* Determine what data in the content area, if any, is being dragged.
*
* aWindow - the window containing the target node
* aTarget - the mousedown event target that started the drag
* aSelectionTargetNode - the node where the drag event should be fired
* aIsAltKeyPressed - true if the Alt key is pressed. In some cases, this
* will prevent the drag from occuring. For example,
* holding down Alt over a link should select the text,
* not drag the link.
* aDataTransfer - the dataTransfer for the drag event.
* aCanDrag - [out] set to true if the drag may proceed, false to stop the
* drag entirely
* aSelection - [out] set to the selection being dragged, or null if no
* selection is being dragged.
* aDragNode - [out] the link, image or area being dragged, or null if the
* drag occurred on another element.
*/
static nsresult GetDragData(nsPIDOMWindow* aWindow,
nsIContent* aTarget,
nsIContent* aSelectionTargetNode,
bool aIsAltKeyPressed,
mozilla::dom::DataTransfer* aDataTransfer,
bool* aCanDrag,
nsISelection** aSelection,
nsIContent** aDragNode);
};
// this is used to save images to disk lazily when the image data is asked for
// during the drop instead of when it is added to the drag data transfer. This
// ensures that the image data is only created when an image drop is allowed.
class nsContentAreaDragDropDataProvider : public nsIFlavorDataProvider
{
virtual ~nsContentAreaDragDropDataProvider() {}
public:
NS_DECL_ISUPPORTS
NS_DECL_NSIFLAVORDATAPROVIDER
nsresult SaveURIToFile(nsAString& inSourceURIString,
nsIFile* inDestFile, bool isPrivate);
};
#endif /* nsContentAreaDragDrop_h__ */