View Full Version : Callback from Javascript

18 May 2013, 12:40 AM
Hi All,

I must communicate applet by javascript api.

If Applet has any action, applet call javascript function webphonetojs(varr);

At this point I must callback this varr from GWT method, to show user about the action.

I can send my commands to applet by (JSNI) native methods. But I couldn't get callback from applet.

I want to ask you how can I implement webphonetojs javascript method from GWT, and how can call GWT method.

Working javascript code is following:

<SCRIPT LANGUAGE="javascript">
function webphonetojs(varr)
//todo: handle incoming calls and other events here

function voipRegister(username, password)

document.applets[0].API_Register("", username, password);

function voipCall(number)

document.applets[0].API_Call(-1, number);

function voipHangup()



Colin Alworth
19 May 2013, 6:52 AM
At a glance, this looks like a basic JSNI question, but without more context it is hard to be sure.

If you want to enable those functions in script on the main page to work, you need to export the methods - check out this section for more info: https://developers.google.com/web-toolkit/doc/latest/DevGuideCodingBasicsJSNI#calling

It seems reasonable that you should be able to write those functions above entirely in your GWT code using JSNI - what isn't working about the callbacks? Are you able to debug it? What did you try, and what errors do you get?

Don't forget to reference $doc and $wnd when writing JSNI instead of document and window.