How to use <a4j:jsFunction><a4j:actionparam>
I'm trying to use:
<script type="text/javascript">
function myfunc() {
var param = 4;
alert("OK");
}
</script>
I call the function like this:
<a4j:jsFunction name="myfunc">
<a4j:actionparam name="param" assignTo="#{MyBean.myfield}"/>
</a4j:jsFunction>
But it does not work. In what may be the reason?
Answer
You misunderstood the purpose of <a4j:jsFunction>. It autogenerates a JavaScript function which you can then call from any JavaScript code in your view.
Your example,
<a4j:jsFunction name="myfunc">
<a4j:actionparam name="param" assignTo="#{MyBean.myfield}"/>
</a4j:jsFunction>
will autogenerate the following function
<script>
function myfunc(param) {
// Here some specific JSF Ajax script which assigns "param"
// to a managed bean property #{MyBean.myfield}
}
</script>
You do not need to define it yourself. You only need to invoke it yourself from some JavaScript code elsewhere. For example,
<span onclick="myfunc(4)">click here to set 4 in MyBean.myfield</span>
or
<script>
function someOtherFunction() {
var param = 4;
myfunc(param);
}
</script>
which is in turn to be used like
<span onclick="someOtherFunction()">click here to call someOtherFunction() which will in turn set 4 in MyBean.myfield</span>