本文实例为大家分享了使用SurfaceView实现动画的具体代码,供大家参考,具体内容如下

与自定义view绘图进行对比:

1.view绘图没有双缓冲机制,而surfaceview有

2.view绘图更新时,要全部更新整张图片,而surfaceview可以更新部分区域

3.新线程无法直接更新view绘图,需要handler配合。

鱼儿游动的动画:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:orientation="vertical"
 android:layout_width="match_parent"
 android:layout_height="match_parent">
 <com.example.liuyan.testbutfly.FishView
  android:layout_width="match_parent"
  android:layout_height="match_parent" />
</LinearLayout>

java代码:

public class FishView extends SurfaceView implements SurfaceHolder.Callback{
 private SurfaceHolder holder;
 private UpdateViewThread updatethread;
 private boolean hasSurface;
 private Bitmap back;
 private Bitmap[] fishs;
 private int fishIndex = 0;//绘制第几张鱼
 //鱼的初始位置
 private float fishx = 778;
 private float fishy = 500;
 private float fishSpeed = 6; //鱼的游动速度
 //鱼的游动角度
 private int fishAngle = new Random().nextInt(60);
 Matrix matrix = new Matrix();

 public FishView(Context context) {
  super(context);
  Log.i("mydate" , "开始");
  //获取surfaceview的surfaceholder,并将该类的实例作为其callback
  holder = getHolder();
  holder.addCallback(this);//以自身作为callback,回调方法
  hasSurface = false;
  back = BitmapFactory.decodeResource(context.getResources() , R.drawable.fishbg);//背景
  int[] id = new int[]{R.drawable.fish0 , R.drawable.fish1 , R.drawable.fish2 ,R.drawable.fish3 ,R.drawable.fish4 ,R.drawable.fish5 ,R.drawable.fish6 ,R.drawable.fish7 ,R.drawable.fish8, R.drawable.fish9};
  fishs = new Bitmap[10];
  //初始化 鱼游动的10张图
  for (int i = 0 ; i < 10 ; i++){
   try {
    fishs[i] = BitmapFactory.decodeResource(context.getResources() , id[i]);
   } catch (Exception e){
    e.printStackTrace();
   }
  }
  Log.i("mydate" , "结束");
 }

 public FishView(Context context, AttributeSet attrs) {
  super(context, attrs);
  Log.i("mydate" , "开始");
  //获取surfaceview的surfaceholder,并将该类的实例作为其callback
  holder = getHolder();
  holder.addCallback(this);//以自身作为callback,回调方法
  hasSurface = false;
  back = BitmapFactory.decodeResource(context.getResources() , R.drawable.fishbg);//背景
  int[] id = new int[]{R.drawable.fish0 , R.drawable.fish1 , R.drawable.fish2 ,R.drawable.fish3 ,R.drawable.fish4 ,R.drawable.fish5 ,R.drawable.fish6 ,R.drawable.fish7 ,R.drawable.fish8, R.drawable.fish9};
  fishs = new Bitmap[10];
  //初始化 鱼游动的10张图
  for (int i = 0 ; i < 10 ; i++){
   try {
//    int fishId = (Integer) R.drawable.class.getField("fish" + i).get(null);//反射机制获取图片
//    Log.i("mydate" , " "+ fishId);
    fishs[i] = BitmapFactory.decodeResource(context.getResources() , id[i]);
   } catch (Exception e){
    e.printStackTrace();
   }
  }
  Log.i("mydate" , "结束");
 }


 public void resume(){
  //创建和启动 图片更新线程
  if (updatethread == null){
   updatethread = new UpdateViewThread();
   if (hasSurface == true){
    updatethread.start();
   }
  }
 }

 public void pause(){
  //停止 图像更新线程
  if (updatethread != null){
   updatethread.requestExitAndWait();
   updatethread = null;
  }
 }


 @Override
 public void surfaceCreated(SurfaceHolder holder) { //surfaceview被创建时回调该方法
  hasSurface = true;
  resume(); //开启线程更新
 }

 @Override
 public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {//surfaceview改变时回调该方法
  if (updatethread != null){
   updatethread.onWindowResize(width , height);
  }
 }

 @Override
 public void surfaceDestroyed(SurfaceHolder holder) {//surfaceview销毁时回调该方法
  hasSurface = false;
  pause(); //停止线程更新
 }

 class UpdateViewThread extends Thread{
  //定义图像是否更新完成的标志
  private boolean done;

  public UpdateViewThread() {
   super();
   done = false;
  }

  @Override
  public void run() {
   SurfaceHolder surfaceholder = holder;
   //循环绘制,直到线程停止
   while (!done){
    Canvas canvas = surfaceholder.lockCanvas();//锁定surfaceview,准备绘制
    //绘制背景
    canvas.drawBitmap(back , 0 , 0 , null);
    //鱼游出屏幕外,重新初始化鱼的位置
    if (fishx < 0 ){
     fishx = 778;
     fishy = 500;
     fishAngle = new Random().nextInt(60);
    }
    if (fishy < 0){
     fishx = 778;
     fishy = 500;
     fishAngle = new Random().nextInt(60);
    }
    //用matrix控制鱼的旋转角度和位置
    matrix.reset();
    matrix.setRotate(fishAngle);//下面的位置计算看图片的解释如下:
    matrix.postTranslate(fishx -= fishSpeed * Math.cos(Math.toRadians(fishAngle)) , fishy -= fishSpeed * Math.sin(Math.toRadians(fishAngle)));
    canvas.drawBitmap(fishs[fishIndex++%fishs.length] , matrix , null);
    surfaceholder.unlockCanvasAndPost(canvas);//解锁canvas,渲染绘制图像
    try {
     Thread.sleep(60);
    } catch (Exception e){
     e.printStackTrace();
    }
   }
  }

  public void requestExitAndWait() {
   //将绘制线程 标记为完成 ,并合并到主线程中
   done = true;
   try {
    join();
   } catch (Exception e){
    e.printStackTrace();
   }
  }

  public void onWindowResize(int width, int height) {
   //处理surfaceview的大小改变事件
  }
 }

}

位置计算图片解释如下:

Math.toRadians(fishAngle)

先理解这句代码的意思:将0-360的角度制角度转化为pi弧度制角度

鱼儿不停的游动,坐标改变其实就是:

当前的x坐标 - 速度*cos角度 , 当前的y坐标 - 速度*sin角度

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。

02-08 17:57