nsIDragSession 编辑

widget/public/nsIDragSession.idlScriptable Provides support for interacting with an ongoing drag session during a drag and drop operation. Inherits from: nsISupports Last changed in Gecko 2.0 (Firefox 4 / Thunderbird 3.3 / SeaMonkey 2.1)

Method overview

void getData( in nsITransferable aTransferable, in unsigned long aItemIndex );

boolean isDataFlavorSupported( in string aDataFlavor );

Attributes

Attribute	Type	Description
canDrop	boolean	Set the current state of the drag, whether it can be dropped or not. Usually the target "frame" sets this so the native system can render the correct feedback.
dataTransfer	nsIDOMDataTransfer	The data transfer object for the current drag operation.
dragAction	unsigned long	Sets the action (copy, move, link and so on) for the current drag. (See nsIDragService)
numDropItems	unsigned long	Get the number of items that were dropped. Read only.
onlyChromeDrop	boolean	Indicates if the drop event should be dispatched only to chrome. This allows chrome to handle a drag that was refused by content.
sourceDocument	nsIDOMDocument	The document where the drag was started, which will be null if the drag originated outside the application. Useful for determining if a drop originated in the same document. Read only.
sourceNode	nsIDOMNode	The DOM node that was originally dragged to start the session, which will be null if the drag originated outside the application. Read only.
targetSize	nsSize	Sets the current width and height of the drag target area. It will contain the current size of the Frame that the drag is currently in. Native code only!

Methods

getData()

Gets data from a drag and drop operation. Can be called while the drag is in process or after the drop has completed.

void getData(
  in nsITransferable aTransferable,
  in unsigned long aItemIndex
);

Parameters

aTransferable

The transferable for the data to be put into.

aItemIndex

Which of multiple drag items, zero-based. Must be less than numDropItems.

isDataFlavorSupported()

Checks to see if any of the native data on the clipboard matches a given data flavor. If numDropItems is greater than one, there is no indication as to which of the items matches the data flavor.

boolean isDataFlavorSupported(
  in string aDataFlavor
);

Parameters

aDataFlavor

A string representing the MIME type of the data to be matched, such as "text/unicode".

Return value

true if the specified flavor matches any of the native data on the clipboard, otherwise false.