Code Forums - View Single Post - Difficulties with removeAll() on a JFrame

jeff · 04-14-2003, 08:46 AM

Hi,

Notice that when you first add your button, you're adding it to the JFrame's content pane. The content pane is where you're supposed to add components to a JFrame.

see:
http://java.sun.com/docs/books/tutor.../toplevel.html

Later in your application, you're calling removeAll directly on the JFrame. This removes the content pane and other panes mentioned in the above URL. You don't really want to be doing this. Instead, call getContentPane().removeAll(). This will restore the JFrame back to how it was before you added any components.

Then, add your new components to the content pane and call:

invalidate
revalidate
repaint

on it.

So, the body of your actionListener could look like this:

xFrame.getContentPane().removeAll();
xFrame.getContentPane().add(new JLabel("Java is NOT stupid"));
xFrame.getContentPane().invalidate();
xFrame.getContentPane().validate();
xFrame.getContentPane().repaint();

I've tried this with your code and it fixes the problem.

04-14-2003, 08:46 AM	#12 (permalink)
jeff Registered User Join Date: Apr 2003 Posts: 2	Hi, Notice that when you first add your button, you're adding it to the JFrame's content pane. The content pane is where you're supposed to add components to a JFrame. see: http://java.sun.com/docs/books/tutor.../toplevel.html Later in your application, you're calling removeAll directly on the JFrame. This removes the content pane and other panes mentioned in the above URL. You don't really want to be doing this. Instead, call getContentPane().removeAll(). This will restore the JFrame back to how it was before you added any components. Then, add your new components to the content pane and call: invalidate revalidate repaint on it. So, the body of your actionListener could look like this: xFrame.getContentPane().removeAll(); xFrame.getContentPane().add(new JLabel("Java is NOT stupid")); xFrame.getContentPane().invalidate(); xFrame.getContentPane().validate(); xFrame.getContentPane().repaint(); I've tried this with your code and it fixes the problem.