Conditional keyup listener on h:inputText?

Question

I'm using JSF and I'd like to call a listener on an InputText element's keyup events, but only if the input text is longer than 3 chars.

My code is:

<h:inputText id="myId" styleClass="iceInpTxt uppercase" maxlength="15" 
value="#{controller.model.value}">
  <f:ajax event="keyup" listener="#{controller.listener}" render="anotherElement"/>
</h:inputText>

Now I'm checking the text's length in my listener, works perfectly but way to slowly. Is there a workaround, like a conditional listener, which is only called when inputText.length() > 3, in other cases the listener is ignored?

Answer 1

you can simply use a javascript-function that only returns true and hence triggers the listener if your required condition is matched.

<h:inputText id="myId" 

   onkeyup="return checkLength(this)" 

   styleClass="iceInpTxt uppercase" maxlength="15" 
   value="#{controller.model.value}">
     <f:ajax event="keyup" listener="#{controller.listener}" render="anotherElement"/>
 </h:inputText>

javascript:

function checkLength(value){
   return value.length > 3;
}