无法取消工作线程。当执行取消功能时，它仍然执行

Question

这个项目与我目前的问题有关。我想我已经解决了这个问题，但是当我单击按钮时想取消工作线程时，还有另一个问题出现了。doInBackground仍在运行。( printf("Runing" + this.index( 仍在工作( 这些是我的代码：

import java.awt.Color;
import java.util.Random;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.SwingWorker;
public class Robot extends SwingWorker< Void ,Integer> {
public int x;
public static int i = 0;
public int index;
public int y;
public Color color;
public final int speed = 10;
Robot(int x , int y , Color color)
{
this.x = x;
this.y = y;
this.color = color;
this.index = i;
i++;
}
public void move_90()
{
this.y += speed;
}
public void move_270()
{
this.y -= speed;
}
public void move_180()
{
this.x -= speed;
}
public void move_0()
{
this.x += speed;
}
public void move_45()
{
this.x += speed;
this.y += speed;
}
public void move_135()
{
this.x -= speed;
this.y += speed;
}
public void move_225()
{
this.x -= speed;
this.y -= speed;
}
public void move_315()
{
this.x += speed;
this.y -= speed;
}
public void move()
{
Random temp = new Random();
int rand = temp.nextInt(8);
switch(rand + 1)
{
case 1: move_0();
break;
case 2: move_135();
break;
case 3: move_180();
break;
case 4: move_225();
break;
case 5: move_270();
break;
case 6: move_315();
break;
case 7: move_45();
break;
case 8: move_90();
break;
}
}
@Override
protected Void doInBackground() throws Exception {
while(true)
{
System.out.println("Runing" + this.index);
move();
if(this.x < 40) this.x = 40;
if(this.x > PlayField.width - 40) this.x = (PlayField.width - 40);
if(this.y < 40) this.y = 40;
if(this.y > PlayField.height - 40) this.y = (PlayField.height - 40);
try {
Thread.sleep(200);
} catch (InterruptedException ex) {
Logger.getLogger(Robot.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
@Override
protected void done() {
super.done();
System.out.println("done");//To change body of generated methods, choose Tools | Templates.
}
}

这是我的机器人模型类：

import java.awt.Color;
import java.util.LinkedList;
public class RobotModel {
public static final int MAX = 8;
public LinkedList<Robot> model = new LinkedList<Robot>();
public void add_New_Robot()
{
Robot temp = new Robot( 40 , 40 , Color.BLUE);
temp.execute();
model.addFirst(temp);
}
}

这是游戏主类

import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
public class GameMain extends JFrame {
RobotModel a;
PlayField field;
public void Game_Start()
{
a = new RobotModel();
field = new PlayField(500 , 500, Color.yellow);
RobotWorld world = new RobotWorld(a);
world.setPreferredSize(new Dimension(500 , 500));
world.robot_Model.add_New_Robot();
world.robot_Model.add_New_Robot();
world.robot_Model.add_New_Robot();
world.robot_Model.add_New_Robot();
world.robot_Model.add_New_Robot();
world.robot_Model.add_New_Robot();
world.robot_Model.add_New_Robot();
this.setSize(field.width , field.height);
this.setLayout(new GridLayout());
this.add(world);
JButton but = new JButton();
but.setPreferredSize(new Dimension(50, 20));
but.setText("STOP");
but.setVisible(true);
but.addActionListener(new ActionListener()
{
@Override
public void actionPerformed(ActionEvent arg0) {
world.robot_Model.model.get(0).cancel(true);
world.robot_Model.model.remove(0);
}
});
this.add(but);
this.setVisible(true);
world.repaint();
}
public void gameUpdate(){
Thread gameThread = new Thread(){
public void run(){
while(true){
//refresh screen
repaint();
//give other threads time
try{
Thread.sleep(5);
}catch(InterruptedException e){
e.printStackTrace();
}
}
}
};
gameThread.start();
}

public static void main(String args[])
{
GameMain main = new GameMain();
main.Game_Start();
main.gameUpdate();
}
}

这是机器人世界级

import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JPanel;
public class RobotWorld extends JPanel {
public RobotModel robot_Model;
public RobotWorld(RobotModel robot_Model) {
super();
this.robot_Model = robot_Model;
this.setSize(PlayField.width , PlayField.height);
this.setVisible(true);
}
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D graphic = (Graphics2D)g;
for(Robot x : this.robot_Model.model )
{
graphic.setColor(x.color);
graphic.drawOval(x.x, x.y, 40, 40);
}
}
}

这是游戏场类

package com.mycompany.test;
import java.awt.Color;
public class PlayField {
public static int width;
public static int height;
public static Color fill_Color;
PlayField(int width , int height , Color fill_Color)
{
this.width = width;
this.height = height;
this.fill_Color = fill_Color;
}
}

MadProgramer在这里给了我一个很好的例子。如果这不是关于练习的要求，我不会用 SwingWorker 编程

Answer 1

您取消，并表示您可以中断。

但是看看你的doInBackground代码：

@Override
protected Void doInBackground() throws Exception {
while(true)
{
System.out.println("Runing" + this.index);
move();
if(this.x < 40) this.x = 40;
if(this.x > PlayField.width - 40) this.x = (PlayField.width - 40);
if(this.y < 40) this.y = 40;
if(this.y > PlayField.height - 40) this.y = (PlayField.height - 40);
try {
Thread.sleep(200);
} catch (InterruptedException ex) {
Logger.getLogger(Robot.class.getName()).log(Level.SEVERE, null, ex);
}
}
}

我们看到您通过将InterruptedException记录在 ctach 块中来响应中断(这会清除线程上的中断状态(，然后愉快地继续循环。当然，这不会阻止线程。

尝试响应线程的中断状态：

@Override
protected Void doInBackground() throws Exception {
while(!Thread.currentThread().isInterrupted())   // break out of the loop onc ethe thread is interrupted
{
// ... omitted for brevity
try {
Thread.sleep(200);
} catch (InterruptedException ex) {
Thread.currentThread().interrupt();   // catching the exception clears the interrupted state, so we reset it, to break out of the loop.
}
}
}