Re: JavaScript callback from Applet.

Daniel Pitts <>
Thu, 25 Sep 2008 08:20:22 -0700
Daniel Pitts wrote:

Is there a way to pass actual JSObject from JavaScript into an Applet?

I'm attempting something like:
   foo: 'bar',
   baz: function(arg) {
I thought it would work. applets[0] has mayscript enabled, etc...

public class MyApplet extends JApplet {
  public void myMethod(JSObject obj) {
     System.out.println(obj.getMember("foo")}; // prints null."baz", new Object[] {"Joe Bob"}); //does nada.

Is what I'm trying to do possible? I'd rather not pass in Strings if
possible, I'd like to pass in actual JSObjects.


I figured out a work around, not pretty, but it does the trick.
Basically, the JSObject passed to the applet has the right native ID,
but not the correct context. I can fix this by putting it into a
JSObject that does have the correct context, and pulling it back out:

public class MyApplet extends JApplet {
     private JSObject appletTmp;

     public JSObject resolveObject(Object o) {
         final int hashCode = System.identityHashCode(o);
         appletTmp.setMember("toResolve" + hashCode, o);
         return (JSObject) appletTmp.getMember("toResolve" + hashCode);

     public void init() {
         if (appletTmp == null) {
             final JSObject window = JSObject.getWindow(this);
             final String tmpName = "_AppletTmp" +
             window.eval("var "+ tmpName +" = {}");
             appletTmp = (JSObject)window.getMember(tmpName);

     public Object doCallback(Object o) {
       JSObject callback = resolveObject(o);
       System.out.println(callback + "\n" + callback.getMember("foo"));"helped", new Object[] {callback.getMember("foo")});
       return callback;

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