When Control listeners are fired, there is no guarantee that all Control values have been bound to the incoming request. The reason for this behavior is that the #onProcess method fires the listener directly.

The problem this creates is that the listener cannot assume a control will have its value bound. For example the following will not work:

public MyPage extends Page {

    public void onInit() {
Select select1 = new Select("select1");
        select1.setListener(this, "onSelect1");
Select select2 = new Select("select2");
        select2.setListener(this, "onSelect2");
        ...
    }

    public boolean onSelect1() {
        // The call below will return null because select2 have
        // not been processed yet
        select2.getSelectedValues();
    }

    public boolean onSelect2() {
        // The call below will return select1 selected values because
        // select1 have been processed
        select1.getSelectedValues();
    }
}

I have been burned by this before and think we should improve this a little.

By delaying the listener invocation until all controls have been processed should solve this issue. In other words instead of invoking the listener from the #onProcess method, we instead register the listener to the Context, and once all Controls have been processed, we invoke all the registered listeners.