Java Applet 游戏循环停止鼠标/键盘输入？

Question

I got a problem I couldn't get to work after about 2 Hours of trying. I want to have a loop that do 2 Methods (Draw and update) but also listen to Mouse/Keyboard events. I have a loop that Draws and Updates, but does nothing outside of the loop ( Listening to events ) I tried alot of things but nothing worked. Help Please?

I tried using the Runnable Thread, using different orders, using wait() and notify(), I've tried alot of things. But basicly I want to know how to run a loop and still check for User Input

Also when I try to quit the program clicking the red "X", it won't quit but still work

Here's the Code:

import java.applet.Applet;
import java.awt.*;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

public class main extends Applet implements MouseListener, Runnable {

    public main() {
        super();
        init();
    }
    Thread t;
    Screen screen = new Screen();
    String Text = "Hello";
    boolean Running = true;
    boolean Click = false;
    int R = 0x00;
    int G = 0x00;
    int B = 0x00;
    int xpoints[] = {25, 40, 40, 25, 25};
    int ypoints[] = {40, 40, 25, 25, 25};
    int npoints = 5;

    public void run() {
        while (Running) {
            GameLoop();
        }
    }

    public void init() {
        this.addMouseListener(this);
        this.setSize(400, 300); //manually set your Frame's size
        t = new Thread(this);
        t.start();
    }

    public void paint(Graphics g) {
        g.setColor(new Color(R, B, G));
        g.fillPolygon(xpoints, ypoints, npoints);
        Running = true;
        t.run();
    }

    public void mousePressed(MouseEvent e) { //On Mouse Click
        System.exit(0);
    }

    public void mouseReleased(MouseEvent e) {
    }

    public void mouseEntered(MouseEvent e) {
        System.exit(0);
    }

    public void mouseExited(MouseEvent e) {
    }

    public void mouseClicked(MouseEvent e) {
    }

    public boolean keyDown(Event e, int key) {
        return true;
    }

    public void GameLoop() {
        if (Running) {
            if (R != 0xff) {
                R++;
            } else {
                if (G != 0xff) {
                    G++;
                } else {
                    if (B != 0xff) {
                        B++;

                    } else {
                        System.exit(0);
                    }
                }
            }
            try {
                sleep(20);
            } catch (InterruptedException e) {

                e.printStackTrace();
            }
            paint(getGraphics());
        }
    }

    public void sleep(int time) throws InterruptedException {
        Thread.sleep(time, 0);
    }
}

Answer 1

This tutorial should provide some insight as to how your program should be structured. And this one is helpful for the mouse listener.

Issues you should address:
1) You're doing something fishy with the paint method. Why are you calling t.run() in there? The thread t is already running and looping constantly calling the paint() method to redraw the screen. Remove this call and see what you get.

1) The destruction of your thread/applciation is poor. The first example above provides a better way for that to occur

2) You have your System.Exit(0) on mousePressed() with the comment //on mouse click but nothing in mouseClicked() ... it works but its bad convention

3)Having your class named main is extremely poor convention that is both confusing and impractical. Rename your class to something like "Game" or similar.

4) Why declare Screen if you don't use it?

Answer 2

I see that you define a Running variable to be true upon initialization. This variable is used to determine whether or not the game should stop. I, however, don't see any place where you modify the value of this variable to false. This would explain why your game never exits.

As for the the game not working, try debugging the application in an IDE. You should then pay attention to what, if any, Exception are being thrown and the values of any variables you are questioning. Hopefully this will give you insight into the behavior of your app.

Don't forget to update us with any new info you discover so we can help you out along the way.