draggable
Makes the component a drag SOURCE that exports a Transferable when dragged.
exportedActions declares which operations the source offers (a TransferAction TransferHandler action bit-mask, e.g. TransferHandler.COPY, TransferHandler.COPY_OR_MOVE); a drop is permitted only for an operation also accepted by the target. transferable is invoked when a drag begins on the component and returns the data to transfer, or null to start no drag.
The outcome of every export - the completed action, including a MOVE whose data the source should remove - is reported through onExportDone.
Declaring a source takes over the component's export: transferable and exportedActions are what it exports and what it offers, in place of whatever it exported on its own. Its import is left alone - without a dropTarget or a clipboard on the same component, a drop or a paste is handled exactly as the component handles it.
Requires a JComponent target. Composes with dropTarget and clipboard on the same component: all three configure one underlying transfer handler, so a component can be a drag source, a drop target, and clipboard-enabled at once. transferable and exportedActions are read on each drag, so passing fresh values across recompositions takes effect immediately.
Return
this modifier with the drag source declared on it.
Parameters
the operations this source offers, as a TransferAction mask; TransferHandler.NONE leaves the gesture recognized but starts no drag.
produces the exported data; the same value answers a clipboard copy or cut whose operation exportedActions offers, so one exporter drives both directions.