Visible panel Size : cannot get it

Question

Hi,
I'm trying to get the visible size of a JPanel (which is contained in a JScrollPane) but I cannot get the correct values.
I want to know what is the visible size (not the total size I can view by scrolling the pane, just the visible when the window is openned), in order to decide how will place the components inside panel. If you see at the image , I want to know what is the size of the orange panel, assuming there is not scroll bar.
If I use getSize, getPreferred size for this panel or for the viewport of the JScrollPane which contains the orange pane, width and height I get are the total width of buttonPanels (>3000px) plus some more pixels and the height of one buttonPanel (120px) plus some more pixels. The same if I use the size, preferredSize of viewPort of the JScrollPane.
I need to know the value of the panels height and width without scrollbars in order to decide how will show these buttonPanels on that panel. I'm trying to get these values after the JFrame.setVisible(true) but get the values I mentioned above. In case I write it this way
        setExtendedState(NORMAL);
        setVisible(true);
        setExtendedState(MAXIMIZED_BOTH);
        redrawMainPanel(getContentPane());the windowState changes two times and the properties size, preferredSize have been updated, so I get the total width of all buttonPanels and the height ~600 wich is the actual height of that panel for my screen. Even that is not enought because firstly I don't want the total width of the panel, but just that I see on the screen when it opens, not by scrolling it. Same for height. By using twice the setExtendedState I can get the correct height but I think if there were many controls so as vertical scroll bar to be shown, I would get a height greater than that of ~600 px I get now.
Is there any way to have just the size of the orange panel you see on the image?
Thanks in advance!
Edited by: ChristosKorakidis on Aug 1, 2009 2:18 AM

Answer 1

Andre thanks for your help but didn't succeed to get the values
In the constructor of my class there is
       setExtendedState(MAXIMIZED_BOTH);
       setVisible(true);
       redrawMainPanel(getContentPane());The redrawMainPanel is
    private void redrawMainPanel(Container container) {
           for (int i=0;i<container.getComponentCount();i++)
                     if ((container.getComponent(i) instanceof JPanel) && (((JPanel)container.getComponent(i)).getName() == "mainPanel")){
                          redrawPanel((JPanel)container.getComponent(i));
                     else if (container.getComponent(i) instanceof Container){
                          redrawMainPanel(((Container)container.getComponent(i)));
     }and the first line of the redrawPanel() is
System.out.println(((JViewport)component.getParent()).getViewRect().getWidth() + " - " + ((JViewport)component.getParent()).getViewRect().getHeight());I get 0 - 0
I havent implement Scrollable, is that necessary?