Change background and text color of JMenuBar and J

2019-01-19 08:57发布

问题:

How can I set custom background color for JMenuBar and JMenu objects inside it? I tried .setBackgroundColor and it does not work!

回答1:

Create a new class that extends JMenuBar:

public class BackgroundMenuBar extends JMenuBar {
    Color bgColor=Color.WHITE;

    public void setColor(Color color) {
        bgColor=color;
    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2d = (Graphics2D) g;
        g2d.setColor(bgColor);
        g2d.fillRect(0, 0, getWidth() - 1, getHeight() - 1);

    }
}

Now you use this class instead of JMenuBar and set the background color with setColor().



回答2:

You would probably need to change opacity of menu items, ie:

JMenuItem item= new JMenuItem("Test");
item.setOpaque(true);
item.setBackground(Color.CYAN);

You can also achieve that globally using UIManager, for example:

UIManager.put("MenuItem.background", Color.CYAN);
UIManager.put("MenuItem.opaque", true);


回答3:

The simplest way (I can think of) is to change the default values used by the UIManager. This will effect all the menu bars and menu items in the application though...

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class TestMenuBar {

    public static void main(String[] args) {
        new TestMenuBar();
    }

    public TestMenuBar() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException ex) {
                } catch (InstantiationException ex) {
                } catch (IllegalAccessException ex) {
                } catch (UnsupportedLookAndFeelException ex) {
                }

                UIManager.put("MenuBar.background", Color.RED);
                UIManager.put("Menu.background", Color.GREEN);
                UIManager.put("MenuItem.background", Color.MAGENTA);

                JMenu mnu = new JMenu("Testing");
                mnu.add("Menu Item 1");
                mnu.add("Menu Item 2");

                JMenuBar mb = new JMenuBar();
                mb.add(mnu);
                mb.add(new JMenu("Other"));

                JFrame frame = new JFrame("Test");
                frame.setJMenuBar(mb);
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new JPanel());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }

        });
    }

}


回答4:

Simple way to do is by .setBackground(Color.RED) and setOpaque(true)

menubar.setBackground(Color.RED); menu.setBackground(Color.yellow); menubar.setOpaque(true); menu.setOpaque(true);

This will give the color of your choices to both the menubar and menu.



回答5:

Mine only worked when I changed:

    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());

to:

    UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());

Otherwise, the colors remained the same.