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JPanel FlowLayout Force Component Wrap

I have an JPanel that uses by default a FlowLayout manager. I like the advantage of the document style FlowLayout in which I add components one at a time with automatic wrapping but would like a component to force selection of a new line.

I read if I used a BoxLayout I could insert a sort of component return key and force the components to start on a new line. I need guidance regarding my decision and which is a better approach.

I have a JLabel and JTextField on one line and would like to place a JTextArea wrapped inside a JScrollPane below.

Solution
    • Use a combination of FlowLayout and BorderLayout. It's a good idea to nest layouts to get your desired result.
    • The JLabel and the JTextField would go in one JPanel with FlowLayout

    • Then another JPanel with BorderLayout will hold the previous panel at the NORTH position, and the JTextArea with JScrollPane at the CENTER position.

      JPanel topPanel = new JPanel();
JLabel label = new JLabel("Text Field Label");
JTextField jtf = new JTextField(20);
topPanel.add(label);
topPanel.add(jtf);

JPanel bothPanel = new JPanel(new BorderLayout());
JTextArea jta = new JTextArea(20, 40);
bothPanel.add(topPanel, BorderLayout.NORTH);
bothPanel.add(new JScrollPane(jta));

    Have a look at Laying Out Components Within a Container

    enter image description here

    import java.awt.BorderLayout;
import java.awt.Color;

import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class FlowBorderDemo {

    public FlowBorderDemo() {
        JPanel topPanel = new JPanel();
        JLabel label = new JLabel("Text Field Label");
        label.setForeground(Color.white);
        JTextField jtf = new JTextField(20);
        topPanel.add(label);
        topPanel.add(jtf);
        topPanel.setBackground(Color.black);


        JPanel bothPanel = new JPanel(new BorderLayout());
        JTextArea jta = new JTextArea(20, 40);
        JScrollPane scrollPane = new JScrollPane(jta);
        scrollPane.setBorder(BorderFactory.createMatteBorder(3, 0, 0, 0, Color.GRAY));
        bothPanel.add(topPanel, BorderLayout.NORTH);
        bothPanel.add(scrollPane);
        bothPanel.setBorder(BorderFactory.createMatteBorder(3, 8, 3, 8, Color.GRAY));

        JLabel copyLabel = new JLabel("<html>&copy;2014 peeskillet</html>");
        copyLabel.setBackground(Color.LIGHT_GRAY);
        copyLabel.setHorizontalAlignment(JLabel.CENTER);
        bothPanel.add(copyLabel, BorderLayout.PAGE_END);


        JFrame frame = new JFrame();
        frame.add(bothPanel);
        frame.pack();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager
                            .getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException
                        | IllegalAccessException
                        | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                new FlowBorderDemo();
            }
        });
    }
}