Question

我需要在我在此程序中创建的字段中显示文本，该字段在actionEvent中标识，这是RadioButton选择。我很难让选择在现场显示。请帮帮忙？

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

  public class JBasketball {

    public static void main(String args[]) {

      JFrame frame = new JFrame("JBasketball");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

      JTextField field = new JTextField(16);

      JPanel panel = new JPanel(new FlowLayout());

      ButtonGroup group = new ButtonGroup();
        JRadioButton sixers = new JRadioButton("Philadelphia 76ers");
        JRadioButton raptors = new JRadioButton("Toronto Raptors");
        JRadioButton lakers = new JRadioButton("Los Angeles Lakers");
        JRadioButton sonics = new JRadioButton("Seattle Supersonics");
        JRadioButton bullets = new JRadioButton("Baltimore Bullets");

      ActionListener action = new ActionListener() {

        public void actionPerformed(ActionEvent actionEvent) {
          JRadioButton aButton = (JRadioButton) actionEvent.getSource();

           String team = aButton.getText();
  //This is where I need the field to display the team name
           field.setText(team);
        }
      };

      panel.add(sixers);
      group.add(sixers);
      panel.add(raptors);
      group.add(raptors);
      panel.add(lakers);
      group.add(lakers);
      panel.add(sonics);
      group.add(sonics);
      panel.add(bullets);
      group.add(bullets);
      panel.add(field);


      sixers.addActionListener(action);
      raptors.addActionListener(action);
      lakers.addActionListener(action);
      sonics.addActionListener(action);
      bullets.addActionListener(action);
      field.addActionListener(action);

      frame.add(panel);
      frame.setSize(500, 130);
      frame.setVisible(true);
      frame.setLocationRelativeTo(null);
    }
  }

Answer 1

一旦你编译它就可以了。您只需要声明文本字段final

final JTextField field = new JTextField

原因是您正在尝试访问匿名类中的局部变量，并且需要声明final。

您应该注意的其他事项：

在Event Dispatch Thread上运行Swing应用程序。详情请见Initial Threads
我不会像你一样在main完成所有工作。为类创建一个构造函数并在那里完成工作，或者使用一些init方法。并在main中实例化构造函数或调用init方法，它最适合你。

Java：在字段中显示actionEvent

1 个答案: