Blocker Description
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.