在对话框中,如果选中了某个组合,则需要显示一组控件,否则显示另一组控件。即我需要2层,并且当组合被选中/未选中时,我需要在它们之间切换。我怎样才能做到这一点?
CardLayout 为此,如下所示。
import java.awt.BorderLayout; import java.awt.CardLayout; import java.awt.Color; import java.awt.Dimension; import java.awt.EventQueue; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.util.Random; import javax.swing.JComboBox; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; /** @see http://stackoverflow.com/questions/6432170 */ public class CardPanel extends JPanel { private static final Random random = new Random(); private static final JPanel cards = new JPanel(new CardLayout()); private static final JComboBox combo = new JComboBox(); private final String name; public CardPanel(String name) { this.name = name; this.setPreferredSize(new Dimension(320, 240)); this.setBackground(new Color(random.nextInt())); this.add(new JLabel(name)); } @Override public String toString() { return name; } public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { create(); } }); } private static void create() { JFrame f = new JFrame(); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); for (int i = 1; i < 9; i++) { CardPanel p = new CardPanel("Panel " + String.valueOf(i)); combo.addItem(p); cards.add(p, p.toString()); } JPanel control = new JPanel(); combo.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { JComboBox jcb = (JComboBox) e.getSource(); CardLayout cl = (CardLayout) cards.getLayout(); cl.show(cards, jcb.getSelectedItem().toString()); } }); control.add(combo); f.add(cards, BorderLayout.CENTER); f.add(control, BorderLayout.SOUTH); f.pack(); f.setLocationRelativeTo(null); f.setVisible(true); } }