SurfaceView 试用

由于项目需要用到动画效果，如果大量绘制animation，则性能不佳，上网搜了，有surfaceview这个东西（不占用主线程）。因此自己学习了一下，以下demo是实现每个一秒钟绘制显示不同颜色的笑脸。 涉及点：SurfaceView、SurfaceHolder。

一、实现效果：

二、自定义surfaceview类 1、： 继承SurfaceView,实现SurfaceHolder Callback接口。

2、重写构造方法

3、实现三个callback方法：

@Override public void surfaceCreated(SurfaceHolder holder) { } @Override public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { } @Override public void surfaceDestroyed(SurfaceHolder holder) { }

三、整体代码：

public class MySurfaceViewTest extends SurfaceView implements SurfaceHolder.Callback{ private SurfaceHolder mSurfaceHolder; private MyThread mMyThread; private boolean isDraw = false; public MySurfaceViewTest(Context context) { super(context); mSurfaceHolder = this.getHolder(); mSurfaceHolder.addCallback(this); mMyThread = new MyThread(); } private class MyThread extends Thread { @Override public void run() { while (isDraw) { try { sleep(1000);//睡一秒钟 drawUI(); } catch (Exception e) { } } super.run(); } } private void drawUI() { Canvas canvas = null; try { canvas = mSurfaceHolder.lockCanvas(); synchronized (mSurfaceHolder) { drawCanvas(canvas); } } finally { if (canvas != null) { mSurfaceHolder.unlockCanvasAndPost(canvas); } } } private void drawCanvas(Canvas canvas) { // 在 canvas 上绘制需要的图形 if (canvas != null) { Log.d("weiwei","come-----------------------------------------------"); canvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR); // 清空界面 Paint p = new Paint(); p.setColor(CircleTextImageUtil.getRandomColor());// 设置随机颜色 // //画笑脸弧线 p.setStyle(Paint.Style.STROKE);//设置空心 RectF oval1=new RectF(150,20,180,40); canvas.drawArc(oval1, 180, 180, false, p);//小弧形 oval1.set(190, 20, 220, 40); canvas.drawArc(oval1, 180, 180, false, p);//小弧形 oval1.set(160, 30, 210, 60); canvas.drawArc(oval1, 0, 180, false, p);//小弧形 } } static class CircleTextImageUtil { /** * Get the random color. * * @return */ private static int getRandomColor() { List<Integer> colorList = new ArrayList<Integer>(); colorList.add(Color.RED); colorList.add(Color.BLUE); colorList.add(Color.GREEN); colorList.add(Color.WHITE); colorList.add(Color.YELLOW); colorList.add(Color.GRAY); return colorList.get((int) (Math.random() * colorList.size())); } } @Override public void surfaceCreated(SurfaceHolder holder) { isDraw = true; mMyThread.start(); } @Override public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { } @Override public void surfaceDestroyed(SurfaceHolder holder) { isDraw = false; } }

引用：

public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); CrashReport.initCrashReport(getApplicationContext(), "077d3ebb59", false); MySurfaceViewTest mySurfaceViewTest = new MySurfaceViewTest(this); // setContentView(R.layout.activity_main); setContentView(mySurfaceViewTest); } }