FocusLost event/navigatedOutColumn to non-DACF controls

Question

In the textAreaControl source I see:
// Focus Listener implementation
* This method is an implementaion side effect
public void focusLost(FocusEvent event)
When I do a focus lost event off the property panel in Designer... and add code to simply do a System.out.println("Focus Lost") on the control... nothing happens when I move to another control and the textareacontrol lost focus.
The correct approach seems to be use the NavigatedOutColumn event which does fire. ( hurrah! )...
BUT.... as I had a suspicion... if I enter into a DACF control, and then click in a NON-DACF control ( in this case, a secondary plain jtextfield password confirmation field )... neither FocusLost nor NavigatedOutColumn fires.
It sorta makes sense, because we haven't navigated into a new Column. ( Is this a terminology conflict/level mix problem? It seems to be relating Column to a rowSetInfo AttributeInfo / EO/VO attribute?
Note that, at least in my case, there are PLENTY of non DACF controls. Particularly JButtons.
As mentioned before, I avoided ButtonControls because I had no DataItemName to associate with 'em... which seemed to cause grief in other places ( in my memory using 3.O ). I actually went back and changed all the ButtonControls I had to JButtons.
This puts me into a rather interesting quandary... or is it safe in 3.2/JRE1.3 to use ButtonControls with no property set for the DataItemName()?
TIA

Answer 1

You are being tripped up by two things. One is a bug and the other is a difference between the 3.2 and 9i (aka 5.0) versions of the NavigationManager. The ComponentNavigationMonitor is OK though. Both of these can be worked around using the ComponentNavigationManager though the resultant code will not be compatible with the code released in the next version of JDeveloper. The solution is to rewrite the focusGained() method and write the new method _applyEdits(). The rewritten and new methods are below in a new version of the class. Notice the package name change; it is now in a new package called oracle.dacf.unsupported. This way, you can just change the package name when the next version is released:
<code>
// oracle/dacf/unsupported/ComponentNavigationMonitor.java
// Oracle JDeveloper
// Copyright (c) 2001 by Oracle Corporation
// All rights reserved.
package oracle.dacf.unsupported;
// imports
import java.awt.Component;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import javax.swing.SwingUtilities;
import oracle.dacf.control.ApplyEditsListener;
import oracle.dacf.control.ApplyEditsValidationException;
import oracle.dacf.control.Control;
import oracle.dacf.control.NavigationManager;
** The ComponentNavigationMonitor allows a Component, AWT or Swing,
** to be used in an application and still have the DAC navigation and
** validation event framework generate the proper events at the
** appropriate times. Normally, non-Control components can not
** participate in the DAC navigation and validation event framework
** because they don't have the mechanisms to notify the framework that
** the focus has moved.
** This class is implemented as a singleton and could be hooked into every
** non-Control Component that is displayed on the screen. It should not be
** attached to DAC Controls because these classes already contain the
** functionality contained in this class. Attaching this class to a DAC
** Control will minimally result in double navigation and validation
** eventing with the resultant performance degradation. Redundant
** navigation and validation could also result in anomalous application
** behavior.
** The DAC design-time and runtime framework does not automatically
** register non-Controls with the ComponentNavigationMonitor because of
** the ambiguity surrounding when this should be done. If the components
** are constructed using a Factory design pattern, then the factory would
** be the optimal place to attach this listener. If your application
** doesn't use this approach then you will have to individually hook each
** component. (Sorry, but there is no way around this fact.) You might
** try something like what the following code fragment illustrates in the
** method that instantiates the component:
** <blockquote>
** <code>
** TextField dateWidget =
** new TextField((new Date()).toLocaleString());
** ComponentNavigationMonitor.observe(dateWidget);
** </code>
** </blockquote>
** For example, if JDeveloper was used to generate code, via either the
** DAC wizards or the visual designer, then you would place this code in
** the jbInit() method of the panel or frame.
** @author Donald King
public class ComponentNavigationMonitor
extends FocusAdapter
private NavigationManager nm;
private static ComponentNavigationMonitor monitor;
private static Object observeGate = new Object();
private static final boolean _DEBUG = true;
private ComponentNavigationMonitor()
} // ComponentNavigationMonitor
** Responds to the gaining of focus by a component.
** This method is responsible for causing validation to be performed and
** restoring forcus to the proper control if validation fails.
public void focusGained(FocusEvent evt)
Control ctrl;
if (nm == null)
nm = NavigationManager.getNavigationManager();
ctrl = nm.getFocusedControl();
// the getChangeLevel() parameters are reversed to workaround
// bug 1678351; fixed for 9i (aka 5.0)
if (ctrl != null &&
!_applyEdits(ctrl) &&
!nm.validateFocusedControl(nm.getChangeLevel(null,ctrl)))
Component c = ctrl.getComponent();
// Paranoia is a good thing; the following is expensive, only do
// it if we must
if (c != null)
SwingUtilities.invokeLater(new DelayedFocus(c));
else
// move the NavigationManager into the proper state so that it
// can properly respond to the next control that gains focus
nm.validateFocusChange(null);
** This functionality is embedded in the 9i (aka 5.0) version of
** NavigationManager.validateFocusedControl(int changeLevel)
private boolean _applyEdits(Control ctrl)
boolean ok = true;
if (ctrl instanceof ApplyEditsListener)
try
((ApplyEditsListener)ctrl).applyEdits();
catch(ApplyEditsValidationException aeve)
ok = false;
return(ok);
** Registers the ComponentNavigationMonitor as a FocusListener.
public static void observe(Component c)
synchronized(observeGate)
if (monitor == null)
monitor = new ComponentNavigationMonitor();
c.addFocusListener(monitor);
** Unregisters the ComponentNavigationMonitor as a FocusListener.
public static void unobserve(Component c)
synchronized(observeGate)
if (monitor == null)
monitor = new ComponentNavigationMonitor();
c.removeFocusListener(monitor);
private class DelayedFocus
implements Runnable
private Component pending;
DelayedFocus(Component c)
pending = c;
public void run()
if (pending != null)
pending.requestFocus();
private void _debug(String s)
if (_DEBUG)
System.out.println("ComponentNavigationMonitor: " + s);
} // _debug
} // ComponentNavigationMonitor
// oracle/dacf/unsupported/ComponentNavigationMonitor.java
// Oracle JDeveloper
// Copyright (c) 2001 by Oracle Corporation
// All rights reserved.
</code>