Java Swing - 如何使JComboBox可編輯為其他值
我們想知道如何使JComboBox可編輯為其他值。
import java.awt.Dimension;
import java.awt.FlowLayout;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Main {
public static void main(String[] args) {
Object[] items = new Object[] { "Dog", "Cat", "Other" };
DefaultComboBoxModel dcbm = new DefaultComboBoxModel(items);
JComboBox comboBox = new JComboBox(dcbm);
comboBox.setPreferredSize(new Dimension(200, 20));
comboBox.addItemListener(e -> {
Object selectedItem = comboBox.getSelectedItem();
boolean editable = selectedItem instanceof String
&& ((String) selectedItem).equals("Other");
comboBox.setEditable(editable);
});
comboBox.getEditor().addActionListener(e -> {
Object newItem = comboBox.getEditor().getItem();
DefaultComboBoxModel d = (DefaultComboBoxModel) comboBox.getModel();
d.addElement(newItem);
d.setSelectedItem(newItem);
});
JPanel content = new JPanel(new FlowLayout());
content.add(new JLabel("Test:"));
content.add(comboBox);
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setContentPane(content);
frame.pack();
frame.setVisible(true);
}
}
【jcombobox】
