JFrame不可关闭，尽管有frame。setDefaultCloseOperation（）

Question

我遇到了一个问题，面板没有加载到JFrame中，JFrame本身没有设置默认的关闭操作，而是执行setSize（）和setVisible（）。我尝试过在main、run（）方法和框架的构造函数中运行框架初始化，但没有区别。MouseListener似乎不起作用，但如果不将面板添加到框架中，就无法确定这一点。我发布这个问题的主要目的是在点击x时关闭框架，并再次将面板添加到框架中。我确信这在游戏状态下不是问题。buffer（）或gameStae。油漆（g）。这是一款名为《当猪飞翔》的电子游戏。以下是代码：

主要类别：

package when.pigs.fly;

public class Main {
    static Frame frame;
    public static void main(String[] args) {
        frame=new Frame();
        frame.panel.run();
    }
}

框架类：

package when.pigs.fly;

import javax.swing.JFrame;

public class Frame extends JFrame{
    Panel panel;
    int windowWidth,windowHeight;
    public Frame(){
        super("When Pigs Fly");
        
        panel=new Panel();
        panel.setListeners();
        
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(1000,600);
        buffer();
        
        add(panel);
        setVisible(true);
    }
    
    public final void buffer(){
        windowWidth=getContentPane().getWidth();
        windowHeight=getContentPane().getHeight();
    }
}

面板类：

package when.pigs.fly;

import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import javax.swing.JPanel;
import static when.pigs.fly.GameState.gameState;
import static when.pigs.fly.Main.frame;

public class Panel extends JPanel implements MouseListener,MouseMotionListener{
    private long timeElapsed;
    int mouseX,mouseY;
    boolean mouseDown;
    
    public Panel(){
        gameState=new GameState(1);
    }
    
    public final void setListeners(){
        addMouseListener(this);
        addMouseMotionListener(this);
    }
    
    public void run(){
        boolean run=true;
        while(run){
            long timeAtStart=System.nanoTime();
            
            if(timeElapsed>=33333333){
                gameState.buffer();
                frame.buffer();
                timeElapsed-=33333333;
            }
            repaint();
            
            timeElapsed+=System.nanoTime()-timeAtStart;
        }
    }
    
    @Override
    public void paintComponent(Graphics g){
        super.paintComponent(g);
        gameState.paint((Graphics2D)g);
    }
    
    @Override
    public void mouseClicked(MouseEvent me) {
        
    }

    @Override
    public void mousePressed(MouseEvent me) {
        mouseDown=true;
    }

    @Override
    public void mouseReleased(MouseEvent me) {
        mouseDown=false;
    }

    @Override
    public void mouseEntered(MouseEvent me) {}

    @Override
    public void mouseExited(MouseEvent me) {}

    @Override
    public void mouseDragged(MouseEvent me) {
        mouseX=me.getX();
        mouseY=me.getY();
    }

    @Override
    public void mouseMoved(MouseEvent me) {
        mouseX=me.getX();
        mouseY=me.getY();
    }

}

Answer 1

怀疑无处不在，但根据您的描述，我怀疑您的run方法正在阻止事件调度线程。

Swing是单线程，不是线程安全的。这意味着您不应该在事件调度线程的上下文中运行长时间运行或阻塞代码，也不应该更新事件调度线程外部UI依赖的UI或任何状态。

有关更多详细信息，请参阅Swing中的并发。

一个简单的解决方案是使用SwingTimer，例如...

import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;

public class Main {
    public static void main(String[] args) {
        new Main();
    }

    public Main() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                JFrame frame = new JFrame();
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel {

        private Timer timer;
        private int mouseX, mouseY;
        private boolean mouseDown;

        public TestPane() {
            MouseHandler handler = new MouseHandler();
            addMouseListener(handler);
            addMouseMotionListener(handler);
        }

        protected void start() {
            if (timer != null) {
                return;
            }
            timer = new Timer(5, new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                    // Check input
                    // Update game state
                    repaint();
                }
            });
            timer.start();
        }

        protected void stop() {
            if (timer == null) {
                return;
            }
            timer.stop();
            timer = null;
        }

        @Override
        public void addNotify() {
            super.addNotify();
            start();
        }

        @Override
        public void removeNotify() {
            super.removeNotify();
            stop();
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(1000, 600);
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            Graphics2D g2d = (Graphics2D) g.create();
            int dotSize = 6;
            if (mouseDown) {
                g2d.setColor(Color.RED);
                g2d.fillOval(mouseX - dotSize, mouseY - dotSize, dotSize * 2, dotSize * 2);
            } else {
                g2d.setColor(Color.BLACK);
                g2d.drawOval(mouseX - dotSize, mouseY - dotSize, dotSize * 2, dotSize * 2);
            }
            g2d.dispose();
        }

        protected class MouseHandler extends MouseAdapter {

            @Override
            public void mousePressed(MouseEvent me) {
                mouseDown = true;
            }

            @Override
            public void mouseReleased(MouseEvent me) {
                mouseDown = false;
            }

            @Override
            public void mouseDragged(MouseEvent me) {
                mouseX = me.getX();
                mouseY = me.getY();
            }

            @Override
            public void mouseMoved(MouseEvent me) {
                mouseX = me.getX();
                mouseY = me.getY();
            }
        }

    }
}