how to call JSNI function from Javascript function?

Question

Here is caller button samples in html:

<input type='button' value='Call' onclick='Test()'>

And here are some functions I tried and which were not worked:

<script type="text/javascript">
    function Test() {
        com.tests.client.Test_GoogleWeb_JSNI::Callee()();
    }
</script>

But we are not able to call Callee().How we can achieve this?I mean how we can invoke JSNI function from javascript?

Help would be appreciated.

Answer 1

It's very easy. You need to "export" your function written in GWT (or it can be another JSNI) function.

Here is the relevant documentation: http://code.google.com/webtoolkit/doc/latest/DevGuideCodingBasicsJSNI.html#calling

So in your case:

In your GWT code:

public static void Caller() /*-{ 
   ... 
}-*/

public static native void exportStaticMethod() /*-{
   $wnd.Callee =
      $entry(@com.tests.client.Test_GoogleWeb_JSNI::Callee());
}-*/;

Then you call exportStaticMethod() somewhere, even in your onModuleLoad. << YOU MUST DO THIS

Then you can call Callee() from your handwritten javascript code.

Your code for the button:

<input type='button' value='Call' onclick='$wnd.Callee();'>

Answer 2

For chrome, the above solution works if I change onclick='$wnd.Callee() to onclick='window.Callee(). Chrome's browser console tells us $wnd is not defined. $wnd is how to access the browser's window object in JSNI.

Sorry I couldn't just leave this as a comment (not enough points)

Answer 3

See here :

1. Make sure that Test_GoogleWeb_JSNI.Callee() is static .
2. Assign the Callee()-function to the window object.