Java Swing - 如何在Action事件處理程序中從JComboBox中獲取選定項目
我們想知道如何在Action事件處理程序中從JComboBox中獲取選定項目。
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Main extends JPanel {
public Main() {
String[] comboTypes = { "Numbers", "Alphabets", "Symbols" };
JComboBox<String> comboTypesList = new JComboBox<>(comboTypes);
comboTypesList.setSelectedIndex(2);
comboTypesList.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
JComboBox jcmbType = (JComboBox) e.getSource();
String cmbType = (String) jcmbType.getSelectedItem();
System.out.println(cmbType);
}
});
setLayout(new BorderLayout());
add(comboTypesList, BorderLayout.NORTH);
}
public static void main(String s[]) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setContentPane(new Main());
frame.pack();
frame.setVisible(true);
}
}
【jframe】
