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Cannot use f:valueChangeListener or f:actionListener with custom component?

 
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Hi, the J2EE tutorial says:


You do not need to create a custom component in these cases:
  .....
   
You need to register event listeners on components. You can either register event listeners on components using the f:valueChangeListener and f:actionListener tags, or you can point at an event-processing method on a managed bean using the component’s actionListener or valueChangeListener attributes. See Implementing an Event Listener and Writing Managed Bean Methods for more information.



I think we can still use event listeners with custom components. In the Core JSF book, chapter 11, the example shows this:


<corejsf: spinner ...>
  <f:valueChangeListener .../>
</corejsf:spinner>


The spinner is a custom component that extends UIInput class.
 
Himai Minh
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Hi,
To answer my own question, I modified an example from memorynotfound at https://memorynotfound.com/jsf-custom-input-facescomponent-example/.
I found out that I cannot add an action listener to the custom component, UIInput.
Because the parent source is not an action source even thought the custom component has a command button.


@FacesComponent(value = "com.memorynotfound.jsf.CustomInput")
public class CustomInput extends UIInput {

 ...
   @Override
   public void encodeEnd(FacesContext context) throws IOException {
       String clientId = getClientId(context);
       char sep = UINamingContainer.getSeparatorChar(context);
       encodeInputField(context, clientId + sep + "inputfield");
       encodeSubmitButton(context, clientId + sep + "submit");
       encodeOutputField(context);
   }

   private void encodeInputField(FacesContext context, String clientId) throws IOException {
       ResponseWriter writer = context.getResponseWriter();
       writer.startElement("input", this);
       writer.writeAttribute("type", "text", null);
       writer.writeAttribute("name", clientId, "clientId");
       writer.writeAttribute("size", "30", null);
       Object value = getValue();
       if (value != null) {
           writer.writeAttribute("value", value.toString(), "value");
       }
       writer.writeAttribute("size", "6", null);
       writer.endElement("input");
   }

   private void encodeSubmitButton(FacesContext context, String clientId) throws IOException {
       ResponseWriter writer = context.getResponseWriter();
       writer.startElement("input", this);
       writer.writeAttribute("type", "Submit", null);
       writer.writeAttribute("name", clientId, "clientId");
       writer.writeAttribute("value", "Click Me!", null);
       writer.endElement("input");
   }

...

}




I did this:


<custom:custom-input>
   <f:actionListener type="com.memorynotfound.jsf.MyActionListener"/>
</custom:custom-input>


I got an error saying :<f:actionListener> Parent is not of type ActionSource, type is: com.memorynotfound.jsf.CustomInput@5b8c3387

So, that proves that custom component does not work with listener like the JEE tutorial says.
 
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