How do i check for Onevent javascript function whether it returns true or False ? Because basically what iam trying to do is to restrict the listener method call based on the Javascript return value .

The following code returns syntax error in Firebug .

 <f:ajax event="keyup" render="@form" onevent="return validatePageNumber(event);" listener="#{bean.listenerMethod}"/>

So How can i determine return value and based onthat the lister method should fire .Thanks in advance :)

How do i check for Onevent javascript function whether it returns true or False ? Because basically what iam trying to do is to restrict the listener method call based on the Javascript return value .

The following code returns syntax error in Firebug .

 <f:ajax event="keyup" render="@form" onevent="return validatePageNumber(event);" listener="#{bean.listenerMethod}"/>

So How can i determine return value and based onthat the lister method should fire .Thanks in advance :)

• javascript
• ajax
• jsf-2
• listener

• Bind you ponent's desired behaviour with "if (!validatePageNumber()) return false;" and enclose within your ponent tag the f:ajax tag. That way you'll be able to intercept the execution basing on your JavaScript code. – skuntsel Commented Feb 26, 2013 at 15:08

1 Answer 1

The onevent attribute must specify a JS function reference name, not a whole JS script. The proper usage of the onevent attribute is

<f:ajax ... onevent="functionName" />

(yes, without parentheses!)

with

function functionName(data) {
    alert(data.status); // Will show 3 times.
}

However, it's clearly the wrong tool for the purpose you had in mind. The onevent should merely reference a listener function which would be invoked 3 times: one before the ajax request is sent, one after the ajax response is arrived, one after the HTML DOM is updated based on ajax response. For proper real world usage examples, see among others Proccess onclick function after ajax call <f:ajax> and Disable/enable mandbutton on ajax event.

Just use the parent ponent's onXXX attribute instead (where XXX is exactly that <f:ajax event> you'd like to hook on). E.g. asusming that it's an <h:inputText>:

<h:inputText ... onkeyup="return validatePageNumber(event)">
     <f:ajax event="keyup" render="@form" />
</h:inputText>