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javaswingalignmentjpaneljlabel

Java: vertical alignment within JPanel


I am trying to vertically align (center) both JLabels inside one JPanel.

JPanel panel = new JPanel();
panel.setPreferredSize(size);
JLabel label1 = new JLabel(icon);
JLabel label2 = new JLabel("text");
panel.add(label1);
panel.add(label2);

I have tried using setAligmentY() with no success. Both labels always appear on the top of JPanel.

UPD: Labels should be located next to each other like using FlowLayout, but in the middle of the JPanel.


Solution

  • Use a GridBagLayout with the default constraints. Here is a small demo code:

    import java.awt.GridBagConstraints;
    import java.awt.GridBagLayout;
    
    import javax.swing.JFrame;
    import javax.swing.JLabel;
    import javax.swing.JPanel;
    import javax.swing.SwingUtilities;
    
    public class TestVerticalAlignement {
    
        protected void initUI() {
            final JFrame frame = new JFrame();
            frame.setTitle("Test vertical alignement");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            JPanel panel = new JPanel();
            panel.setLayout(new GridBagLayout());
            GridBagConstraints gbc = new GridBagConstraints();
            JLabel label1 = new JLabel("label1");
            JLabel label2 = new JLabel("label2");
            panel.add(label1, gbc);
            panel.add(label2, gbc);
            frame.add(panel);
            frame.setSize(300, 300);
            frame.setVisible(true);
        }
    
        public static void main(String[] args) {
            SwingUtilities.invokeLater(new Runnable() {
                @Override
                public void run() {
                    new TestVerticalAlignement().initUI();
                }
            });
        }
    
    }