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[英]How can I add the ActionEvent to the JButton so that when i click it it will fire the event?
[英]how to declare JLabels within actionListener(actionEvent e) so that Text can be set when JButton is clicked
我正在编写一个剪刀石头布游戏,我试图让每个 JLabels 在三个按钮(Rock、Paper、Scissors)中的一个被点击时更新。
这样做的问题是每个 JLabels 都在 createWindow() 中定义,我需要它们也在 ActionListener(ActionEvent e) 中定义。
我试图从 createWindow() 和 JLabels 更新中复制粘贴一些代码,但唯一的问题是它创建了一个全新的 window 没有按钮(仅包含文本)。 如果我尝试在主要方法之外实例化标签,则 JLabels 根本不会出现。
感谢任何帮助(无论我是否必须重新编写整个程序),我是 Java 和 Swing 的新手,任何批评都会以某种方式有所帮助。 (我在 Eclipse IDE 中写作)。
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class RockPaperScissors extends JPanel implements ActionListener {
public static void main(String[] args) {
RockPaperScissors sm = new RockPaperScissors();
sm.createWindow();
}
private void createWindow() {
// create JFrame/JPanel
JFrame frame = new JFrame("Rock! Paper! Scissors!");
JPanel panel = new JPanel();
JLabel title = new JLabel("Rock! Paper! Scissors!");
JLabel playerchoice = new JLabel("");
JLabel computerdecision = new JLabel("");
JLabel outcome = new JLabel("");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.pack();
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
JButton button1 = new JButton("Rock");
panel.add(button1);
button1.addActionListener(this);
button1.setBounds(480, 500, 100, 50);
JButton button2 = new JButton("Paper");
panel.add(button2);
button2.addActionListener(this);
button2.setBounds(590, 500, 100, 50);
JButton button3 = new JButton("Scissors");
panel.add(button3);
button3.addActionListener(this);
button3.setBounds(700, 500, 100, 50);
frame.add(panel);
panel.setLayout(new BorderLayout());
GroupLayout layout = new GroupLayout(this);
this.setLayout(layout);
panel.add(title);
panel.add(playerchoice);
panel.add(computerdecision);
panel.add(outcome);
outcome.setBounds(571, 90, 260, 200);
computerdecision.setBounds(571, 100, 260, 200);
playerchoice.setBounds(571, 120, 260, 200);
title.setBounds(571, 0, 260, 200);
}
public void actionPerformed(ActionEvent e) {
// JLabels
int choice = 0;
int computerchoice = 0;
int min = -1;
int max = -3;
computerchoice = (int) (Math.random() * (max - min - 1) + min);
if (computerchoice == -1) {
panel.add(computerdecision);
computerdecision.setText("The Computer Chose Rock!");
// for checking
System.out.println("The Computer Chose Rock!");
} else if (computerchoice == -2) {
panel.add(computerdecision);
computerdecision.setText("The Computer Chose Paper!");
// for checking
System.out.println("The Computer Chose Paper!");
} else if (computerchoice == -3) {
panel.add(computerdecision);
computerdecision.setText("The Computer Chose Scissors!");
// for checking
System.out.println("The Computer chose Scissors!");
}
if (e.getActionCommand().equals("Rock")) {
choice = 1;
panel.add(playerchoice);
playerchoice.setText("You chose Rock!");
// for checking
System.out.println("You chose Rock!");
} else if (e.getActionCommand().equals("Paper")) {
choice = 2;
panel.add(playerchoice);
playerchoice.setText("You chose Paper!");
// for checking
System.out.println("You chose Paper!");
} else if (e.getActionCommand().equals("Scissors")) {
choice = 3;
panel.add(playerchoice);
playerchoice.setText("You chose Scissors!");
// for checking
System.out.println("You chose Scissors!");
}
if (choice + computerchoice == 0) {
panel.add(outcome);
outcome.setText("It is a Tie!");
// for checking
System.out.println("It is a Tie!");
} else if (choice + computerchoice == 1 || choice + computerchoice == -2) {
panel.add(outcome);
outcome.setText("You Win!");
// for checking
System.out.println("You Win!");
} else if (choice + computerchoice == 2 || choice + computerchoice == -1) {
panel.add(outcome);
outcome.setText("You Lose...");
// for checking
System.out.println("You Lose...");
}
}}
解决你的问题的方法很简单,只需将outcome
class 的panel
, playerchoice
, computerdecision
和RockPaperScissors
成员改为像这样的局部变量
public class RockPaperScissors extends JPanel implements ActionListener {
private JPanel panel;
private JLabel computerdecision;
private JLabel playerchoice;
private JLabel outcome;
...
private void createWindow() {
JFrame frame = new JFrame("Rock! Paper! Scissors!");
panel = new JPanel();
playerchoice = new JLabel("");
computerdecision = new JLabel("");
outcome = new JLabel("");
JLabel title = new JLabel("Rock! Paper! Scissors!");
...
}
...
}
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