menuexample.java

来自「java swing 开发代码」· Java 代码 · 共 74 行

//  MenuExample.java
// A simple example of constructing and using menus.
//

package	jswing.ch14;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;

public class MenuExample extends JPanel {

    public JTextPane pane;
    public JMenuBar menuBar;

    public MenuExample() {
        menuBar = new JMenuBar();
        JMenu formatMenu = new JMenu("Justify");
        formatMenu.setMnemonic('J');

        MenuAction leftJustifyAction = new MenuAction("Left",
                                           new ImageIcon("left.gif"));
        MenuAction rightJustifyAction = new MenuAction("Right",
                                           new ImageIcon("right.gif"));
        MenuAction centerJustifyAction = new MenuAction("Center",
                                           new ImageIcon("center.gif"));
        MenuAction fullJustifyAction = new MenuAction("Full",
                                           new ImageIcon("full.gif"));

        JMenuItem item;
        item = formatMenu.add(leftJustifyAction);
        item.setMnemonic('L');
        item = formatMenu.add(rightJustifyAction);
        item.setMnemonic('R');
        item = formatMenu.add(centerJustifyAction);
        item.setMnemonic('C');
        item = formatMenu.add(fullJustifyAction);
        item.setMnemonic('F');

        menuBar.add(formatMenu);
        menuBar.setBorder(new BevelBorder(BevelBorder.RAISED));

    }

    class MenuAction extends AbstractAction {
   
        public MenuAction(String text, Icon icon) {
            super(text,icon);
        }

        public void actionPerformed(ActionEvent e) {
            try { pane.getStyledDocument().insertString(0 ,
                  "Action ["+e.getActionCommand()+"] performed!\n", null);
            } catch (Exception ex) { ex.printStackTrace(); } 
        }
    }

    public static void main(String s[]) {

        MenuExample example = new MenuExample();
        example.pane = new JTextPane();
        example.pane.setPreferredSize(new Dimension(250, 250));
        example.pane.setBorder(new BevelBorder(BevelBorder.LOWERED));

        JFrame frame = new JFrame("Menu Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setJMenuBar(example.menuBar);
        frame.getContentPane().add(example.pane, BorderLayout.CENTER);
        frame.pack();
        frame.setVisible(true);
    }
}