Question

如何设置JComboBox下拉框高度

我用netBeans做的界面，JComboBox下拉框的内容是后添加进去的，用.addItem。可是下拉框的高度却是1行，只能看到一条选项。焦点移开后再点击就正常了。
问题：有没有办法指定这个下拉框的高度或者让它自动调整为最适合的？

Answer 1

给你个例子，对照一下看看。
再不行把源码发来看看

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

public class ComboBoxTest {
public static void main(String[] args) {
ComboBoxFrame frame = new ComboBoxFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}

class ComboBoxFrame extends JFrame {

private JComboBox faceCombo;
private JLabel label;
private static final int DEFAULT_SIZE = 12;

public ComboBoxFrame() {
setTitle("ComboBoxTest");
setSize(300,200);

label = new JLabel("The quick brown fox jumps over the lazy dog.");
label.setFont(new Font("Serif", Font.PLAIN, DEFAULT_SIZE));
add(label, BorderLayout.CENTER);

faceCombo = new JComboBox();
faceCombo.setEditable(true);
faceCombo.addItem("Serif");
faceCombo.addItem("SansSerif");
faceCombo.addItem("Monospaced");
faceCombo.addItem("Dialog");
faceCombo.addItem("DialogInput");

faceCombo.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event) {
label.setFont(new Font((String)faceCombo.getSelectedItem(), Font.PLAIN, DEFAULT_SIZE));
}
});

JPanel comboPanel = new JPanel();
comboPanel.add(faceCombo);
add(comboPanel, BorderLayout.SOUTH);
}
}

Answer 2

你是不是默认只显示第一个的？如果你把所有的都放进去，应该都显示的