Android在SurfaceView做动画一般方法

MainActivity

package com.example.surfacemove;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;

public class MainActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(new MyView(this));//指定界面
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }

    
}

MyView

package com.example.surfacemove;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;

public class MyView extends SurfaceView implements Runnable, Callback {

    private Paint paint;
    private Canvas canvas;
    private boolean isRunning = true;//标志新线程是否运行
    private SurfaceHolder sh;
    private int i;

    public MyView(Context context) {
        super(context);
        paint = new Paint();
        paint.setStyle(Style.STROKE);
        paint.setColor(Color.GREEN);
        paint.setAntiAlias(true);
        sh = getHolder();//得到surfaceholder
        sh.addCallback(this);//添加回调
    }

    public void surfaceChanged(SurfaceHolder holder, int format, int width,
            int height) {//界面改变时调用

    }

    public void surfaceCreated(SurfaceHolder holder) {//界面创建后调用
        new Thread(this).start();//开启新线程
    }

    public void surfaceDestroyed(SurfaceHolder holder) {//界面销毁后调用
        isRunning = false;//标志位置为假
    }

    public void run() {//run函数
        while (isRunning) {//如果标志位为真
            i++;
            if(i==50){
                i=0;
            }
            drawView();//画画面
            try {
                Thread.sleep(100);//延时
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    private void drawView() {//画画函数
        try {
            if(sh!=null){//若sh不为空
                canvas = sh.lockCanvas();//得到canvas
                canvas.drawColor(Color.BLACK);//清屏
                canvas.drawCircle(100, 100, i, paint);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }finally{
            if(canvas!=null){//若canvas不为空
                sh.unlockCanvasAndPost(canvas);//解锁canvas
            }
        }
    }
}