ExternalInterface: pass object reference across interface - how?

I want to invoke methods on specific Javascript or
ActionScript objects through calls across the ExternalInterface
barrier. I would like to be able to do this either AS -> JS or
JS -> AS.
So I would like to pass an object reference across the
interface. I'm not sure exactly what *is* getting passed (is it the
serialized value of the object?), but it doesn't seem to work as an
object reference.
Here's a notional code sample. I have two symmetric object
definitions, one in Javascript, one in ActionScript. During
initialization, one instance of each object will be created and
given a pointer to the other. Then they should each be able to
invoke a method on the other to "do stuff".
//----------[ code ]---------------------------------
//--- Javascript ---
class JSobj {
var _asObj;
JSobj.prototype.setASObj = function(obj) { _asObj = obj; }
JSobj.prototype.callASObj = function(foo) {
callASObjectMethod(_asObj, foo); } // does: _asObj.asMethod(foo);
JSobj.prototype.jsMethod = function(bar) { /* do stuff */ }
function callJSObjectMethod(obj, args) { obj.jsMethod(args);
//--- ActionScript ---
class ASobj {
var _jsObj;
public function set jsObj (obj:Object):void { _jsObj = obj;
public function callJSObj (foo:Number):void {
ExternalInterface.call("callJSObjectMethod", _jsObj, foo); } //
does: _jsObj.jsMethod(foo);
public function asMethod (bar:Number):void { /* do stuff */
function callASObjectMethod (obj:Object, args) {
obj.asMethod(args); }
ExternalInterface.addCallback("callASObjectMethod",
callASObjectMethod);
//----------[ /code ]---------------------------------
My workaround is to pass a uint as an opaque handle for the
object, then resolve it when it is passed back. I'd rather pass a
real reference if possible. Is there a way to pass object
references between JS and AS?
Thanks,
-e-

It's an object of a class that extends Object. I guess the answer is no then.
Thanks for your answer

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    ~

  • Calrification on Pass by reference

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    > In java, if we are passing an object to a function
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    -- Arnold, K., Gosling J., Holmes D. (2006). The Java� Programming Language Fourth Edition. Boston: Addison-Wesley.

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    gerard

  • How do I get an activeX object reference from a LabVIEW ActiveXContainer ref?

    How do I get an activeX object reference from a LabVIEW ActiveXContainer ref?
    I'm trying to control an ActiveX object (a Web Browser) from another VI and need to get the object reference programmatically. I can get the LabVIEW ActiveXContainer reference, but am lost on how to get the reference for the object _inside_ the container.

    Hi Lee,
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    - Philip Courtois, Thinkbot Solutions
    Attachments:
    WebContainer.zip ‏21 KB

  • Drag and Drop - Transferable, how to pass a reference? (URGENT)

    I've a tree that supports drag and drop correctly but every time I exchange a node position the old parent instance remaining on the tree is different from the one I was referencing with the dragged child before the drag occurred. I absolutely need to maintain all references and cannot work with copies.
    Is there any way to use the Transferable interface to pass the original object instead of a copy?
    Thanks to Tedhill who raised the problem, trying to get a quick answer.
    ;o)

    hi guys let me close this thread:
    Thanks to asjf and sergey35 who helped me.
    Actually the isDataFlavorSupported method you suggest passes a reference and not a copy.
    Too bad I fell into another problem with the reloading of the
    moving-node Object after the DnD.
    But finally the working code is:
    public class XJTreeDnD extends XJTree implements DragGestureListener, DragSourceListener, DropTargetListener{
      private DefaultMutableTreeNode dragNode = null;
      private TreePath dragParentPath = null;
      private TreePath dragNodePath = null;
      private DragSource dragSource;
      private DropTarget dropTarget;
      private TransferableTreePath transferable;
      private boolean DnDEnabled = true;
      //private boolean CnPEnabled = false;
      public XJTreeDnD(XNode node) {
        super(node);
        // Set up the tree to be a drop target.
        dropTarget = new DropTarget(this, DnDConstants.ACTION_MOVE, this, true);
        // Set up the tree to be a drag source.
        dragSource = DragSource.getDefaultDragSource();
        dragSource.createDefaultDragGestureRecognizer(this, DnDConstants.ACTION_MOVE, this);
      private DefaultMutableTreeNode getTreeNode(Point location) {
        TreePath treePath = getPathForLocation(location.x, location.y);
        if (treePath != null) {
          return((DefaultMutableTreeNode) treePath.getLastPathComponent());
        } else {
          return(null);
    //dragGesture implementation
        public void dragGestureRecognized(DragGestureEvent e) {
          if(DnDEnabled){
            TreePath path = this.getSelectionPath();
            if (path == null || path.getPathCount() <= 1) {
              System.out.println("Error: Path null, or trying to move the Root.");
              return;
            dragNode = (DefaultMutableTreeNode) path.getLastPathComponent();
            dragNodePath = path;
            dragParentPath = path.getParentPath();
            transferable = new TransferableTreePath(path);
            // Start the drag.
            e.startDrag(DragSource.DefaultMoveDrop, transferable, this);
    //dragSource implementation
        public void dragDropEnd(DragSourceDropEvent e) {
          try {
            if (e.getDropSuccess()) {
              ((BaseXJTreeModel)this.getModel()).removeNodeFromParent(dragNode);
              DefaultMutableTreeNode dragParent = (DefaultMutableTreeNode) dragParentPath.getLastPathComponent();
              XNode xnodeParent = (XNode)dragParent.getUserObject();
              ((BaseXJTreeModel)this.getModel()).valueForPathChanged(dragParentPath, xnodeParent);
          } catch (Exception ex) {
            ex.printStackTrace();
        public void dragEnter(DragSourceDragEvent e) {
          // Do Nothing.
        public void dragExit(DragSourceEvent e) {
          // Do Nothing.
        public void dragOver(DragSourceDragEvent e) {
          // Do Nothing.
        public void dropActionChanged(DragSourceDragEvent e) {
          // Do Nothing.
    //dropTarget implementation
        public void drop(DropTargetDropEvent e) {
          try {
            Point dropLocation = e.getLocation();
            DropTargetContext dtc = e.getDropTargetContext();
            XJTreeDnD tree = (XJTreeDnD) dtc.getComponent();
            TreePath parentPath = tree.getClosestPathForLocation(dropLocation.x, dropLocation.y);
            DefaultMutableTreeNode parent = (DefaultMutableTreeNode)parentPath.getLastPathComponent();
            Transferable data = e.getTransferable();
            DataFlavor[] flavors = data.getTransferDataFlavors();
            for (int i=0;i<flavors.length;i++) {
              if (data.isDataFlavorSupported(flavors)) {
    e.acceptDrop(DnDConstants.ACTION_MOVE);
    TreePath movedPath = (TreePath) data.getTransferData(flavors[i]);
    DefaultMutableTreeNode treeNodeMoved = (DefaultMutableTreeNode) movedPath.getLastPathComponent();
    DefaultMutableTreeNode treeNodeLeft = (DefaultMutableTreeNode) this.dragNodePath.getLastPathComponent();
    XNode xnodeParent = (XNode)parent.getUserObject();
    XNode xnodeChild = (XNode)treeNodeLeft.getUserObject();
    /** @todo check the parent whether to allow the drop or not */
    if(xnodeParent.getPath().startsWith(xnodeChild.getPath())){
    System.out.println("cannot drop a parent node on one of its children");
    return;
    if(xnodeParent.getPath().getPath().equals((xnodeChild.getPath().getParentPath()))){
    System.out.println("node is already child of selected parent");
    return;
    // Add the new node to the current node.
    xnodeParent.addChild(xnodeChild);
    ((BaseXJTreeModel)this.getModel()).valueForPathChanged(parentPath, xnodeParent);
    ((BaseXJTreeModel)this.getModel()).insertNodeInto(treeNodeMoved, parent, parent.getChildCount());
    ((BaseXJTreeModel)this.getModel()).valueForPathChanged(movedPath, xnodeChild);
    e.dropComplete(true);
    } else {
    System.out.println("drop rejected");
    e.rejectDrop();
    } catch (IOException ioe) {
    ioe.printStackTrace();
    } catch (UnsupportedFlavorException ufe) {
    ufe.printStackTrace();
    public void dragEnter(DropTargetDragEvent e) {
    if (isDragOk(e) == false) {
    e.rejectDrag();
    return;
    e.acceptDrag(DnDConstants.ACTION_MOVE);
    public void dragExit(DropTargetEvent e) {
    // Do Nothing.
    public void dragOver(DropTargetDragEvent e) {
    Point dragLocation = e.getLocation();
    TreePath treePath = getPathForLocation(dragLocation.x, dragLocation.y);
    if (isDragOk(e) == false || treePath == null) {
    e.rejectDrag();
    return;
    // Make the node active.
    setSelectionPath(treePath);
    e.acceptDrag(DnDConstants.ACTION_MOVE);
    public void dropActionChanged(DropTargetDragEvent e) {
    if (isDragOk(e) == false) {
    e.rejectDrag();
    return;
    e.acceptDrag(DnDConstants.ACTION_MOVE);
    private boolean isDragOk(DropTargetDragEvent e) {
    /** @todo gestire i casi in cui il drop non sia concesso */
    return (true);
    public void setDragAndDropEnabled(boolean enabled){
    this.DnDEnabled = enabled;
    public boolean isDragAndDropEnabled(){
    return this.DnDEnabled;
    Thanks again.
    flat

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