[JAVA] Refreshing after replacing a JPanel.

[Arcane Wizard]

I'm working on a task management tool and the GUI currently looks like this, on the left is a JScrollPane containing a "TaskTree" (extends JTree), and on the right is a simple empty JPanel I'll refer to as "contentPanel".

For a summary, read this line:
I want the user to be able to select a Task from the TaskTree and see the corresponding form in the contentPanel, this needs to be so dynamic that I must be able to replace the JPanel with one stored in the Task.

Now, I have a "Task" class that extends DefaultMutableTreeNode, which basically is just a DefaultMutableTreeNode with a JPanel stored in it as well. Since the Tasks are loaded into the TaskTree from that Task class, the TaskTree can access the JPanel stored in such a Task. I assigned a TreeSelectionListener to TaskTree, and it catches events in the tree correctly.

So what I want to do in the event of the user clicking on a Task is that the TreeSelectionListener replaces the contentPanel with the JPanel stored in that Task.

Now, it can access that JPanel just fine, I can get all it's properties and show them in the console from within the TreeSelectionListener. It can also access the contentPanel and change it's background color for example.

this one:
So, in order to replace contentPanel with the Task's JPanel, I simply do:
contentPanel = task.getPanel();

So now contentPanel points to the JPanel stored in the Task. This works correctly so far, since showing contentPanel's properties now shows the properties of the JPanel I replaced it with.

And the rest:
However, on the screen, nothing seems to happen. I think this is because the contentPanel isn't refreshed as it would be when I where to change the background colour (which works, and yes, I can change contentPanel's background colour to the background colour of Task's JPanel) and I know one would normally use [url="http://java.sun.com/j2se/1.4.2/docs/api/javax/swing/JComponent.html#revalidate()"]revalidate()[/url] to refresh a JPanel after adding a Button for example.

However, revalidate() does not seem to help, so I was wondering if anybody here could.

Never mind, I figured it out. Removing it from it's parent and then adding the new one works, though I had tried that.
Container parent = contentPanel.getParent();
JPanel taskPanel = task.getPanel();
parent.remove( contentPanel );
parent.add( taskPanel );

Overkill in my honest opinion, but it's clean and it works.
contentPanel = taskPanel;