Android GLSurfaceView學習（1）：屏幕清理程序，使用隨機顏色刷屏

1.實現GLSurfaceView.Renderer接口：
static class SimpleRender implements GLSurfaceView.Renderer{
    Random random = new Random();
     @Override
     public void onSurfaceCreated(GL10 gl10, EGLConfig eglConfig) {
        //設置材質和紋理
        }
    @Override
    public void onSurfaceChanged(GL10 gl10, int i, int i1) {
    //每當界面大小需要調整時就會調用，輸入參數包括新界面的寬和高，以像素爲單位
    }
    @Override
    public void onDrawFrame(GL10 gl10) {//隨機顏色清屏
    gl10.glClearColor(random.nextFloat(), random.nextFloat(), random.nextFloat(), 1);
    gl10.glClear(GL10.GL_COLOR_BUFFER_BIT);
    }
    }
    2.調用
    GLSurfaceView glSurfaceView ；
     @Override
      protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      glSurfaceView = new GLSurfaceView(this);
       glSurfaceView.setRenderer(new SimpleRender());
       setContentView(glSurfaceView);
       }

     @Override
    protected void onResume() {
        super.onResume();
        glSurfaceView.onResume();
    }
    @Override
    protected void onPause() {
        super.onPause();
        glSurfaceView.onPause();
    }