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Name: rmT116609 Date: 10/10/2000 java version "1.3.0" Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.0-C) Java HotSpot(TM) Client VM (build 1.3.0-C, mixed mode) I've written a JTree that supports drag&drop. I implemented the DropTargetListener.dragOver(DropTargetDragEvent) that it selects the current node that the dragging node moves over. Now, I want to check if this current/selected node is a valid drop target (node). For this reason, I need to get the current transferable to check wether source and target nodes are "compatible". For this reason I did a DropTargetDragEvent.getTransferable() (just like DropTargetDropEvent.getTransferable()) but this method is not available in DropTargetDragEvent! Playing with different DataFlavors is not enough, there are objects of the same flavour but with different properties. And the dropping sequence is dependend on this properties, so I need to have the transferable to check for additional values. Can we expect to have DropTargetDragEvent.getTransferable() in the next SDK or is there another solution for this problem? when I implemented the DropTargetListener, I came to dragOver(). In this method I want to check if the dragged node is allowed to be dropped on the current "under" node. SO, just like I did in with a DropTargetDropEvent, I called "getTransferable()" to inspect the nodes and do further checking. But the compiler said that getTransferable() is not availabe in DropTargetDragEvent! But I need this to check whether the node is "compatible" with the to be dropped on node. (Application logic: only specific nodes (with specific properties) are allowed to be dropped - even of the same falvour!). Here's the code with the not working (but needed) part in comments: -------------------------------------- /** * Implements DropTargetListener. * Called when a drag operation is ongoing on the DropTarget. */ public void dragOver(DropTargetDragEvent event) { //System.out.println("DropTargetListener.dragOver() ..."); Point mouseLoc = event.getLocation(); TreePath path = this.getPathForLocation(mouseLoc.x, mouseLoc.y); if (path != null) { VegasNode selectedTarget = (VegasNode) path.getLastPathComponent(); selectNode(selectedTarget); //unfortunately, the following method does not exist: !!! // Transferable tr = event.getTransferable(); // if (tr.isDataFlavorSupported(VegasNode.NODE_FLAVOR)) { //is this a VegasNode? // VegasNode dragNode = (VegasNode) tr.getTransferData(VegasNode.NODE_FLAVOR); // Utils.debug("check here for valid drop sequence: dragNode="+dragNode+", dropNode="+selectedTarget); // //todo: check type of both VegasNodes if they are compatibe ... // } } }//dragOver() (Review ID: 107743) ======================================================================
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