How do I display two JPanels in the ‘North’ in borderlayout?
Here’s and example code that outputs a GUI with three distinct rows, Top, Middle, Bottom. There’s one button covering the first row, 3 buttons covering the second row, and one covering the bottom row.
package borderLayoutDemo; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JPanel; import java.awt.BorderLayout; public class BorderLayoutDemo { public static void main(String[] args) { JFrame.setDefaultLookAndFeelDecorated(true); JFrame fj = new JFrame("Demonstration of Border Layout"); fj.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); JButton jbtn1 = new JButton("UP"); JButton jbtn2 = new JButton("DOWN"); JButton jbtn3 = new JButton("LEFT"); JButton jbtn4 = new JButton("RIGHT"); JButton jbtn5 = new JButton("MIDDLE"); JPanel pnl = new JPanel(); pnl.setLayout(new BorderLayout()); pnl.add(jbtn1, BorderLayout.NORTH); pnl.add(jbtn2, BorderLayout.SOUTH); pnl.add(jbtn3, BorderLayout.WEST); pnl.add(jbtn4, BorderLayout.EAST); pnl.add(jbtn5, BorderLayout.CENTER); fj.add(pnl); fj.pack(); fj.setVisible(true); } }
Output of above code: output of above code
However, I’d like there to be two jpanels in the North section so it’d make 4 “rows” like this:
|---------------button--------------| //north |---------------button2-------------| //north ----------------center--------------- //center |---------------button3-------------| //south
I’ve tried simply just adding it as follows:
pnl.add(jbtn1, BorderLayout.NORTH); pnl.add(jbtn2, BorderLayout.NORTH);
But what happens here is the second button just replaces the first one:
|---------------button2-------------| //north ----------------center--------------- //center |---------------button3-------------| //south
How would I get two rows in the north layout area?
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Answer
Creating a more complex GUI is straightforward when you think of a GUI as a JFrame
with as many JPanels
as necessary to define the GUI.
Here’s the GUI you were looking for.
I created a JPanel
for each section of the JFrame
(NORTH, CENTER, and SOUTH). Each of those JPanels
used a BorderLayout
so that when you expand the GUI, the NORTH and SOUTH buttons stay the same height.
Here’s the complete runnable example code.
import java.awt.BorderLayout; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.SwingUtilities; public class BorderLayoutDemo implements Runnable { public static void main(String[] args) { SwingUtilities.invokeLater(new BorderLayoutDemo()); } @Override public void run() { JFrame fj = new JFrame("Demonstration of Border Layout"); fj.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); fj.add(createNorthPanel(), BorderLayout.NORTH); fj.add(createCenterPanel(), BorderLayout.CENTER); fj.add(createSouthPanel(), BorderLayout.SOUTH); fj.pack(); fj.setLocationByPlatform(true); fj.setVisible(true); } private JPanel createNorthPanel() { JPanel panel = new JPanel(new BorderLayout()); JButton button1 = new JButton("North Button"); panel.add(button1, BorderLayout.NORTH); JButton button2 = new JButton("North Button 2"); panel.add(button2, BorderLayout.SOUTH); return panel; } private JPanel createCenterPanel() { JPanel panel = new JPanel(new BorderLayout()); JButton button = new JButton("Center Button"); panel.add(button, BorderLayout.CENTER); return panel; } private JPanel createSouthPanel() { JPanel panel = new JPanel(new BorderLayout()); JButton button = new JButton("South Button"); panel.add(button, BorderLayout.SOUTH); return panel; } }