focustraversalexample.java

java swing 开发代码

//FocusTraversalExample.java
// Similar to the FocusExample, this class uses the custom AlphaButtonPolicy
// focus traversal policy to navigate another small set of buttons.
//
package	jswing.ch28;

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

public class FocusTraversalExample extends JPanel {

    public FocusTraversalExample() {
        setLayout(new GridLayout(6, 1));
        JButton button1 = new JButton("Texas");
        JButton button2 = new JButton("Vermont");
        JButton button3 = new JButton("Florida");
        JButton button4 = new JButton("Alabama");
        JButton button5 = new JButton("Minnesota");
        JButton button6 = new JButton("California");

        setBackground(Color.lightGray);
        add(button1);
        add(button2);
        add(button3);
        add(button4);
        add(button5);
        add(button6);
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame("Alphabetized Button Focus Traversal");
        frame.setFocusTraversalPolicy(new AlphaButtonPolicy());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setContentPane(new FocusTraversalExample());
        frame.setSize(400, 300);
        frame.setVisible(true);
    }
}