Thread: Need help with very specific panel layout

Hi there.

For the last couple of days I tried to lay out a panel in a specific way but no layoutManager I picked was able to get it quite right.
So I am asking here whether someone can suggest to me what kind of layout manager(s) to use for this.

Here is a picture of how the end result should look like:
Layout.jpg

It looks like the BorderLayout is the perfect choice, but the problem is, when I use the BorderLayout the top panel will never grow in height as rows are needed.
The top will always have a fixed height of only a single row.

I have also tried other layout managers most were not able to fix the top panels height, others had problems with the size restrictions on the toolbar or came with other problems.

I would very much appreciate any advice on this, thank you very much.

I do not know why the top and bottom panels are not correctly growing in height. I have prepared an SSCCE, but it uses the MigLayout for the toolbar constraints. I hope this is not a problem:

public class LayoutTest extends JPanel {
 
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					JFrame frame = new JFrame();
					frame.setContentPane(new LayoutTest());
					frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}
 
	public LayoutTest() {
		setLayout(new BorderLayout(0, 0));
 
		JPanel top = new JPanel();
		add(top, BorderLayout.NORTH);
 
		for (int i = 0; i < 20; i++) {
			JButton newBtn = new JButton("Button: "+i);
			top.add(newBtn);
		}
 
		JPanel btm = new JPanel();
		add(btm, BorderLayout.SOUTH);
 
		for (int i = 0; i < 20; i++) {
			JButton newBtn = new JButton("Button: "+i);
			btm.add(newBtn);
		}
 
		JPanel center = new JPanel();
		add(center, BorderLayout.CENTER);
		center.setLayout(new MigLayout("", "[75%,grow][25%,grow]", "[grow]"));
 
		JPanel body = new JPanel();
		center.add(body, "cell 0 0,grow");
 
		JToolBar toolBar = new JToolBar();
		center.add(toolBar, "cell 1 0,grow");
 
		JTabbedPane tabbedPane = new JTabbedPane(JTabbedPane.TOP);
		toolBar.add(tabbedPane);
 
		JPanel panel = new JPanel();
		tabbedPane.addTab("New tab", null, panel, null);
 
		JPanel panel_2 = new JPanel();
		tabbedPane.addTab("New tab", null, panel_2, null);
 
		JPanel panel_1 = new JPanel();
		tabbedPane.addTab("New tab", null, panel_1, null);
 
	}
 
}

This is even more intersting since the FlowLayout claims that it would add additional Rows as needed.
I will see if I can get it to work and update the thread.

--- Update ---

I cant seem to find a LayoutManager that does what the FlowLayout promises. (at least not without a lot of work)
The problem is that I need to be able to dynamically add / remove Components to / from the top panel and have it resized automatically.

Can you give me any suggestion what Layout might do this job without having to write too much code around it?
Alternatively I guess I would create my own Layout which extends the FlowLayout and "fixes" this "feature".

I am sorry, I must have overlooked that. It does indeed look exactly like what I need, thank you.