JTree - Position & Size

Question

I would like to display a JTree within a JScrollPane in JFrame.
My problem is: I can't set the position and size of the scrollPane.
     public void SimpleTree() {
         WindowUtilities.setNativeLookAndFeel();
         addWindowListener(new ExitListener());
         Container content = getContentPane();
         DefaultMutableTreeNode root = readXMLFile();     
         JTree jtree = new JTree(root);
         jtree.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);
         JScrollPane scrollPane  = new JScrollPane(jtree);
         scrollPane.setViewportView(jtree);
           // ? ? ? what do I need in here       
         content.add(scrollPane);
         setVisible(true);
       } I tried a lot, bot It does not working :(
Aykut

Answer 1

Hi Aykut,
The usual way to control the way components appear is to use a LayoutManager, which will allow you to dictate the overall layout for your content Container.
Alternatively, if you want to place the JScrollPane at a specific place and a specific size, you can set the LayoutManager to be null, then use scrollPane.setBounds(...) to prescribe exactly where it will sit.
The problem with the second choice (which appears at first glance to meet your requirements) is that different operating systems, with different native look-and-feels (as you're using) may vary in the exact size of components, borders, etc. and so may look better on one system than on others.
For this reason, I'd take the time to look at the alternative LayoutManagers (you may find that the relatively simple BorderLayout or BoxLayout meets your needs), the added advantage being automatic resizing of your scrollPane when the main window is resized.
I hope this is a helpful start though.
Chris.