Android在屏幕上移动图片代码，,Speed.javapa

Android在屏幕上移动图片代码，,Speed.javapa

Speed.java

package cn.outofmemory.model.components;public class Speed {    public static final int DIRECTION_RIGHT = 1;    public static final int DIRECTION_LEFT  = -1;    public static final int DIRECTION_UP    = -1;    public static final int DIRECTION_DOWN  = 1;    private float xv = 1;   // velocity value on the X axis    private float yv = 1;   // velocity value on the Y axis    private int xDirection = DIRECTION_RIGHT;    private int yDirection = DIRECTION_DOWN;    public Speed() {        this.xv = 1;        this.yv = 1;    }    public Speed(float xv, float yv) {        this.xv = xv;        this.yv = yv;    }    public float getXv() {        return xv;    }    public void setXv(float xv) {        this.xv = xv;    }    public float getYv() {        return yv;    }    public void setYv(float yv) {        this.yv = yv;    }    public int getxDirection() {        return xDirection;    }    public void setxDirection(int xDirection) {        this.xDirection = xDirection;    }    public int getyDirection() {        return yDirection;    }    public void setyDirection(int yDirection) {        this.yDirection = yDirection;    }    // changes the direction on the X axis    public void toggleXDirection() {        xDirection = xDirection * -1;    }    // changes the direction on the Y axis    public void toggleYDirection() {        yDirection = yDirection * -1;    }}

[Java]代码

public void run() {    Canvas canvas;    Log.d(TAG, "Starting game loop");    while (running) {        canvas = null;        // try locking the canvas for exclusive pixel editing        // in the surface        try {            canvas = this.surfaceHolder.lockCanvas();            synchronized (surfaceHolder) {                // update game state                this.gamePanel.update();                // render state to the screen                // draws the canvas on the panel                this.gamePanel.render(canvas);            }        } finally {            // in case of an exception the surface is not left in            // an inconsistent state            if (canvas != null) {                surfaceHolder.unlockCanvasAndPost(canvas);            }        }   // end finally    }}public void update() {    // check collision with right wall if heading right    if (droid.getSpeed().getxDirection() == Speed.DIRECTION_RIGHT            && droid.getX() + droid.getBitmap().getWidth() / 2 >= getWidth()) {        droid.getSpeed().toggleXDirection();    }    // check collision with left wall if heading left    if (droid.getSpeed().getxDirection() == Speed.DIRECTION_LEFT            && droid.getX() - droid.getBitmap().getWidth() / 2 <= 0) {        droid.getSpeed().toggleXDirection();    }    // check collision with bottom wall if heading down    if (droid.getSpeed().getyDirection() == Speed.DIRECTION_DOWN            && droid.getY() + droid.getBitmap().getHeight() / 2 >= getHeight()) {        droid.getSpeed().toggleYDirection();    }    // check collision with top wall if heading up    if (droid.getSpeed().getyDirection() == Speed.DIRECTION_UP            && droid.getY() - droid.getBitmap().getHeight() / 2 <= 0) {        droid.getSpeed().toggleYDirection();    }    // Update the lone droid    droid.update();}