Unlike Richfaces where you can directly call javascript function, primefaces you need to have javascript function as:
function_name(xhr, status, args)
Using listed CommandButton as Example:
In function test.testfxn() we have:
public void testfxn(){
RequestContext reqCtx = RequestContext.getCurrentInstance();
i = i++;
reqCtx.addCallbackParam("i", i);
}
Here,In function call to backing bean from actionlistener the variables are added to RequestContext.
Now In javascript function:
function draw(xhr, status, args) {
console.log("We are into draw function");
jsonString = JSON.parse(args.i); //json variable is taken out from args variable.
console.log("The value of i "+ i);
}