如何在 Java 中暂停和恢复计时器

Question

我有一个小游戏，我需要在用户按下暂停按钮时暂停计时器，然后在用户按下恢复按钮时恢复计时器并继续增加秒数。我研究了很多，尝试了不同的解决方案，但 none 对我有用。你能帮我实现这个功能吗？这是我的代码：

public class App {

private JTextField timerHours;
private JTextField timerMinutes;
private JTextField timerSeconds;
private Timer timer = new Timer();
private long  timeElapsedInSeconds = 0;
private JButton playButton;

public static void main(String[] args) {
        EventQueue.invokeLater(() -> {
            try {
                App window = new App();
            } catch (Exception e) {
                e.printStackTrace();
            }
        });
    }

private App() {
   initializeWindow();
   createTimer();
}

private void createTimer() {

        timer.schedule(new TimerTask() {
            @Override
            public void run() {
                timeElapsedInSeconds += 1;
                System.out.println("Elapsed seconds: " + timeElapsedInSeconds);
                timerSeconds.setText(String.valueOf(timeElapsedInSeconds % 60));
                timerMinutes.setText(String.valueOf((timeElapsedInSeconds / 60) % 60));
                timerHours.setText(String.valueOf((timeElapsedInSeconds / 60) / 60));
            }
        }, 1000, 1000);
    }

private void initializeWindow() {

  JPanel bottom_panel = new JPanel();
  bottom_panel.setLayout(null);

        // Create Pause button
        JButton pauseButton = new JButton("Pause");
        pauseButton.setBounds(10, 20, 90, 25);
        pauseButton.addActionListener(actionEvent -> {
            // Pause the game
            timer.cancel();
            playButton.setEnabled(true);
            pauseButton.setEnabled(false);
            
        });
        bottom_panel.add(pauseButton);

        // Create Play button
        playButton = new JButton("Play");
        playButton.setBounds(110, 20, 90, 25);
        playButton.setEnabled(false);
        playButton.addActionListener(actionEvent -> {
            // Resume the game and continue the timer from the value saved in `timeElapsedInSeconds`
            playButton.setEnabled(false);
            pauseButton.setEnabled(true);
        });
        bottom_panel.add(playButton);
}

感谢阅读本文。

Answer 1

尝试使用 Swing timer.

    private void createTimer() {
        
        timer = new Timer(1000, (ae)->
        {
                timeElapsedInSeconds += 1;
                System.out.println(
                        "Elapsed seconds: " + timeElapsedInSeconds);
                timerSeconds.setText(
                        String.valueOf(timeElapsedInSeconds % 60));
                timerMinutes.setText(String
                        .valueOf((timeElapsedInSeconds / 60) % 60));
                timerHours.setText(String
                        .valueOf((timeElapsedInSeconds / 60) / 60));
            });
        timer.setDelay(1000);
        timer.start();  // or start it elsewhere
}

然后您可以使用stop()和start()方法来暂停和恢复动作。查看 javaDocs 了解更多详情。

Answer 2

这是完整的代码，谁会需要这样的东西：

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

public class App {
    private JFrame gameFrame;
    private JTextField timerHours;
    private JTextField timerMinutes;
    private JTextField timerSeconds;
    private Timer timer;
    private long timeElapsedInSeconds = 0;
    private JButton playButton;

    public static void main(String[] args) {
        EventQueue.invokeLater(() -> {
            try {
                App window = new App();
                window.gameFrame.setVisible(true);
            } catch (Exception e) {
                e.printStackTrace();
            }
        });
    }

    private App() {
        initializeWindow();
        createTimer();
    }

    private void createTimer() {

        timer = new Timer(1000, (ae) ->
        {
            timeElapsedInSeconds += 1;
            System.out.println("Elapsed seconds: " + timeElapsedInSeconds);
            timerSeconds.setText(String.valueOf(timeElapsedInSeconds % 60));
            timerMinutes.setText(String.valueOf((timeElapsedInSeconds / 60) % 60));
            timerHours.setText(String.valueOf((timeElapsedInSeconds / 60) / 60));
        });
        timer.setDelay(1000);
        timer.start();  // or start it elsewhere
    }

    private void initializeWindow() {

        // Create main window
        gameFrame = new JFrame();
        gameFrame.setFocusable(true);
        gameFrame.requestFocus();
        gameFrame.setFocusTraversalKeysEnabled(false);
        gameFrame.setTitle("My Game");
        gameFrame.setResizable(false);
        gameFrame.setBounds(100, 100, 700, 600);
        gameFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        // Create right panel of main window which will contain the Digital Timer, Console buttons etc
        JPanel right_panel = new JPanel();
        right_panel.setLayout(null);

        // Create bottom panel of main window which will contain the buttons
        JPanel bottom_panel = new JPanel();
        bottom_panel.setLayout(null);

        // Create Digital Timer
        JPanel digital_timer = new JPanel();
        digital_timer.setLayout(new FlowLayout());
        digital_timer.setBounds(30, 10, 100, 60);
        JLabel timer_label = new JLabel("DIGITAL TIMER");
        timer_label.setForeground(Color.black);
        digital_timer.add(timer_label);

        // Create hours textField for digital timer
        timerHours = new JTextField("00");
        timerHours.setEditable(false);
        timerHours.setBackground(Color.black);
        timerHours.setForeground(Color.white);
        digital_timer.add(timerHours);

        JLabel timer_label2 = new JLabel(":");
        timer_label2.setForeground(Color.white);
        digital_timer.add(timer_label2);

        // Create minutes textField for digital timer
        timerMinutes = new JTextField("00");
        timerMinutes.setEditable(false);
        timerMinutes.setBackground(Color.black);
        timerMinutes.setForeground(Color.white);
        digital_timer.add(timerMinutes);

        JLabel timer_label3 = new JLabel(":");
        timer_label3.setForeground(Color.white);
        digital_timer.add(timer_label3);

        // Create seconds textField for digital timer
        timerSeconds = new JTextField("00");
        timerSeconds.setEditable(false);
        timerSeconds.setBackground(Color.black);
        timerSeconds.setForeground(Color.white);
        digital_timer.add(timerSeconds);

        right_panel.add(digital_timer);

        // Create Pause button
        JButton pauseButton = new JButton("Pause");
        pauseButton.setBounds(10, 20, 90, 25);
        pauseButton.addActionListener(actionEvent -> {
            // Pause the game
            timer.stop();
            playButton.setEnabled(true);
            pauseButton.setEnabled(false);
        });
        bottom_panel.add(pauseButton);

        // Create Play button
        playButton = new JButton("Play");
        playButton.setBounds(110, 20, 90, 25);
        playButton.setEnabled(false);
        playButton.addActionListener(actionEvent -> {
            // Run the game
            timer.start();
            playButton.setEnabled(false);
            pauseButton.setEnabled(true);
        });
        bottom_panel.add(playButton);

        // Create a group of layouts (Container) where to put all frames and panels used in this app.
        GroupLayout groupLayout = new GroupLayout(gameFrame.getContentPane());
        groupLayout.setHorizontalGroup(
                groupLayout.createParallelGroup(GroupLayout.Alignment.LEADING)
                        .addGroup(groupLayout.createSequentialGroup()
                                .addPreferredGap(LayoutStyle.ComponentPlacement.RELATED)
                                // Set width dimensions for right panel
                                .addComponent(right_panel, GroupLayout.PREFERRED_SIZE, 150, GroupLayout.PREFERRED_SIZE))
                        // Set width dimensions for bottom panel
                        .addComponent(bottom_panel, GroupLayout.PREFERRED_SIZE, 650, GroupLayout.PREFERRED_SIZE)
        );
        groupLayout.setVerticalGroup(
                groupLayout.createParallelGroup(GroupLayout.Alignment.LEADING)
                        .addGroup(groupLayout.createSequentialGroup()
                                .addGroup(groupLayout.createParallelGroup(GroupLayout.Alignment.LEADING)
                                        //  Set height dimensions for right panel
                                        .addComponent(right_panel, GroupLayout.PREFERRED_SIZE, 500, GroupLayout.PREFERRED_SIZE))
                                // Set height dimensions for bottom panel
                                .addComponent(bottom_panel, GroupLayout.PREFERRED_SIZE, 50, GroupLayout.PREFERRED_SIZE)
                                .addContainerGap(GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
        );

        gameFrame.getContentPane().setLayout(groupLayout);
    }
}

如何在 Java 中暂停和恢复计时器

How to pause and resum a timer in Java

java

swing

timer