让两个球在android中移动

Question

我是一个新的蜜蜂到android开发。我从一个站点得到了一个球运动的代码。它有MovementView.java和UpdateThread.java类。在同一行我尝试通过定义类MovementView1使两个球移动.java和UpdateThread1.java，但我只得到第二个球移动，也可以有人请告诉如何让球在相互冲突时偏转。

这是MainActivity.java

package com.example.movements;
public class MainActivity extends Activity {

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(new MovementView(this));
    setContentView(new MovementView1(this));
}
}

这是MovementView.java

package com.example.movements;
public class MovementView extends SurfaceView implements SurfaceHolder.Callback{
private int xPos;
private int yPos;
private int xVel;
private int yVel;
private int width;
private int height;
private int circleRadius;
private Paint circlePaint;
UpdateThread updateThread;
public MovementView(Context context) {
    super(context);
    getHolder().addCallback(this);
    circleRadius = 10;
    circlePaint = new Paint();
    circlePaint.setColor(Color.BLUE);
    xVel = 2;
    yVel = 2;
}
@Override
protected void onDraw(Canvas canvas) {
    canvas.drawColor(Color.WHITE);
    canvas.drawCircle(xPos, yPos, circleRadius, circlePaint);
}
public void updatePhysics() {
    xPos += xVel;
    yPos += yVel;
    if (yPos - circleRadius < 0 || yPos + circleRadius > height) {
        if (yPos - circleRadius < 0) {
            yPos = circleRadius;
        }else{
            yPos = height - circleRadius;
        }
        yVel *= -1;
    }
    if (xPos - circleRadius < 0 || xPos + circleRadius > width) {
        if (xPos - circleRadius < 0) {
            xPos = circleRadius;
        } else {
            xPos = width - circleRadius;
        }
        xVel *= -1;
    }
}
public void surfaceCreated(SurfaceHolder holder) {
    Rect surfaceFrame = holder.getSurfaceFrame();
    width = surfaceFrame.width();
    height = surfaceFrame.height();
    xPos = width / 2;
    yPos = circleRadius;
    updateThread = new UpdateThread(this);
    updateThread.setRunning(true);
    updateThread.start();
}
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
public void surfaceDestroyed(SurfaceHolder holder) {
    boolean retry = true;
    updateThread.setRunning(false);
    while (retry) {
        try {
            updateThread.join();
            retry = false;
        } catch (InterruptedException e) {
        }
    }
}
}

这是MovementView1.java

package com.example.movements;
public class MovementView1 extends SurfaceView implements SurfaceHolder.Callback{
private int xPos;
private int yPos;
private int xVel;
private int yVel;
private int width;
private int height;
private int circleRadius;
private Paint circlePaint;
UpdateThread1 updateThread;
public MovementView1(Context context) {
    super(context);
    getHolder().addCallback(this);
    circleRadius = 10;
    circlePaint = new Paint();
    circlePaint.setColor(Color.BLUE);
    xVel = 50;
    yVel = 50;
}
@Override
protected void onDraw(Canvas canvas) {
    canvas.drawColor(Color.WHITE);
    canvas.drawCircle(xPos, yPos, circleRadius, circlePaint);
}
public void updatePhysics() {
    xPos += xVel;
    yPos += yVel;
    if (yPos - circleRadius < 0 || yPos + circleRadius > height) {
        if (yPos - circleRadius < 0) {
            yPos = circleRadius;
        }else{
            yPos = height - circleRadius;
        }
        yVel *= -1;
    }
    if (xPos - circleRadius < 0 || xPos + circleRadius > width) {
        if (xPos - circleRadius < 0) {
            xPos = circleRadius;
        } else {
            xPos = width - circleRadius;
        }
        xVel *= -1;
    }
}
public void surfaceCreated(SurfaceHolder holder) {
    Rect surfaceFrame = holder.getSurfaceFrame();
    width = surfaceFrame.width();
    height = surfaceFrame.height();
    xPos = width / 2;
    yPos = circleRadius;
    updateThread = new UpdateThread1(this);
    updateThread.setRunning(true);
    updateThread.start();
}
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
public void surfaceDestroyed(SurfaceHolder holder) {
    boolean retry = true;
    updateThread.setRunning(false);
    while (retry) {
        try {
            updateThread.join();
            retry = false;
        } catch (InterruptedException e) {
        }
    }
}
}

这是UpdateThread.java

package com.example.movements;
public class UpdateThread extends Thread {
private long time;
private final int fps = 20;
private boolean toRun = false;
private MovementView movementView;
private SurfaceHolder surfaceHolder;
public UpdateThread(MovementView rMovementView) {
    movementView = rMovementView;
    surfaceHolder = movementView.getHolder();
}
public void setRunning(boolean run) {
    toRun = run;
}
@Override
public void run() {
    Canvas c;
    while (toRun) {
        long cTime = System.currentTimeMillis();
        if ((cTime - time) <= (1000 / fps)) {
            c = null;
            try {
                c = surfaceHolder.lockCanvas(null);
                movementView.updatePhysics();
                movementView.onDraw(c);
            } finally {
                if (c != null) {
                    surfaceHolder.unlockCanvasAndPost(c);
                }
            }
        }
        time = cTime;
    }
}
}

这是UpdateThread1.java

package com.example.movements;
public class UpdateThread1 extends Thread {
private long time;
private final int fps = 20;
private boolean toRun = false;
private MovementView1 movementView;
private SurfaceHolder surfaceHolder;
public UpdateThread1(MovementView1 rMovementView) {
    movementView = rMovementView;
    surfaceHolder = movementView.getHolder();
}
public void setRunning(boolean run) {
    toRun = run;
}
@Override
public void run() {
    Canvas c;
    while (toRun) {
        long cTime = System.currentTimeMillis();
        if ((cTime - time) <= (1000 / fps)) {
            c = null;
            try {
                c = surfaceHolder.lockCanvas(null);
                movementView.updatePhysics();
                movementView.onDraw(c);
            } finally {
                if (c != null) {
                    surfaceHolder.unlockCanvasAndPost(c);
                }
            }
        }
        time = cTime;
    }
}
}