java – 动态JComboBoxes

我有以下数据(String)：

Course1: A1
Course1: A2
Course2: B1
Course2: B2
Course2: B3
Course2: B4
Course3: C1
Course3: C2

我想创建两个JComboBox(JComboBox1,JComboBox2),以便JComboBox1包含Course1,Course2,Course3等.

如果我从JComboBox1中选择了Course2,则相应的B1,B2,B3,B4应该填入JComboBox2.

如何实现？非常感谢.

解决方法

是的,只需为每个集合创建一个 DefaultComboBoxModel,并在JComboBox1更改时在JComboBox2上执行setModel().

附录：例如,

import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ComboBoxModel;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class ComboTest extends JPanel implements ActionListener,Runnable {

    private final JComboBox combo1 = new JComboBox(
        new String[]{"Course 1","Course 2","Course 3"});
    private final JComboBox combo2 = new JComboBox();
    private ComboBoxModel[] models = new ComboBoxModel[3];

    public Combotest() {
        models[0] = new DefaultComboBoxModel(
            new String[]{"A1","A2"});
        models[1] = new DefaultComboBoxModel(
            new String[]{"B1","B2","B3","B4"});
        models[2] = new DefaultComboBoxModel(
            new String[]{"C1","C2"});

        combo2.setModel(models[0]);
        this.add(combo1);
        this.add(combo2);
        combo1.addActionListener(this);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        int i = combo1.getSelectedindex();
        combo2.setModel(models[i]);
    }

    @Override
    public void run() {
        JFrame f = new JFrame("ComboTest");
        f.setDefaultCloSEOperation(JFrame.EXIT_ON_CLOSE);
        f.add(this);
        f.pack();
        f.setLocationRelativeto(null);
        f.setVisible(true);
    }

    public static void main(String[] args) {
        EventQueue.invokelater(new Combotest());
    }
}