Android实现在屏幕上移动图片的方法
作者：红薯
这篇文章主要介绍了Android实现在屏幕上移动图片的方法,实例分析了Android操作图片的相关技巧,需要的朋友可以参考下
本文实例讲述了Android实现在屏幕上移动图片的方法。分享给大家供大家参考。具体实现方法如下：
1. Speed.java文件：
package net.obviam.droidz.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;
}
}
2. main.java文件：
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();
}
希望本文所述对大家的Android程序设计有所帮助。