问题
A simple question on the title.
My case is that I want to listen to "before RENDER_RESPONSE" phase, and alter some components internal state.
Is PhaseListener the "right way" to do this in SEAM applications?
回答1:
If you want alter JSF component internal state, rely on JSF phase listener. Seam way of declaring JSF phase listener is shown bellow
@Name("applicationPhaseListener")
@Scope(ScopeType.APPLICATION)
public class ApplicationPhaseListener {
/**
* Called TRANSPARENTLY by Seam
*/
@Observer("org.jboss.seam.beforePhase")
public void beforePhase(PhaseEvent event) {
}
/**
* Called TRANSPARENTLY by Seam
*/
@Observer("org.jboss.seam.afterPhase")
public void afterPhase(PhaseEvent event) {
}
}
But if you want to alter Seam contextual component state, use
@Name("applicationPhaseListener")
public class ApplicationPhaseListener {
@Observer("applicationListener")
public void applicationListener() {
}
}
You can
Call your event programatically
Events.instance().raiseEvent("applicationListener");
By using @RaiseEvent annotation which is placed aboved some action method
@RaiseEvent("applicationListener")
public void doSomething() {
}
pages.xml
<page id="<PAGE_ID_GOES_HERE>">
<raise-event type="applicationListener"/>
</page>
来源：https://stackoverflow.com/questions/3809225/what-is-the-official-seam-way-of-listening-to-jsf-seam-phases