[ajax] selectOneMenu ajax events

I am using an editable primefaces selectOneMenu to display some values. If the user selects an item from the List a textarea should be updated. However, if the user types something in the selectOneMenu, the textarea should not be updated.

I thought I could work this with ajax event out. However, I don't know which event I can use here. I only know the valueChange event. Are there any other events, like onSelect or onKeyUp?

Here is my code:

<p:selectOneMenu id="betreff" style="width: 470px !important;"  
            editable="true" value="#{post.aktNachricht.subject}">
            <p:ajax event="valueChange" update="msgtext"
                listener="#{post.subjectSelectionChanged}" />
            <f:selectItems value="#{post.subjectList}" />
</p:selectOneMenu>

<p:inputTextarea style="width:550px;" rows="15" id="msgtext"
        value="#{post.aktNachricht.text}" />

You could check whether the value of your selectOneMenu component belongs to the list of subjects.

Namely:

public void subjectSelectionChanged() {
    // Cancel if subject is manually written
    if (!subjectList.contains(aktNachricht.subject)) { return; }
    // Write your code here in case the user selected (or wrote) an item of the list
    // ....
}

Supposedly subjectList is a collection type, like ArrayList. Of course here your code will run in case the user writes an item of your selectOneMenu list.

Be carefull that the page does not contain any empty component which has "required" attribute as "true" before your selectOneMenu component running.
If you use a component such as

<p:inputText label="Nm:" id="id_name" value="#{ myHelper.name}" required="true"/>

then,

<p:selectOneMenu .....></p:selectOneMenu>

and forget to fill the required component, ajax listener of selectoneMenu cannot be executed.

I'd rather use more convenient itemSelect event. With this event you can use org.primefaces.event.SelectEvent objects in your listener.

<p:selectOneMenu ...>
    <p:ajax event="itemSelect" 
        update="messages"
        listener="#{beanMB.onItemSelectedListener}"/>
</p:selectOneMenu>

With such listener:

public void onItemSelectedListener(SelectEvent event){
    MyItem selectedItem = (MyItem) event.getObject();
    //do something with selected value
}