PathEffect的六个子类：

这六个子类分别可以实现不同的路径效果：

以此往下-------》

CornerPathEffect：

CornerPathEffect mEffects=new CornerPathEffect(50);

DashPathEffect：

DashPathEffect mEffects = new DashPathEffect(new float[] {
   20, 10}, mPhase);

DashPathEffect：

DashPathEffect mEffects = new DashPathEffect(new float[] {
   20, 10, 50, 5, 100, 30, 10, 5}, mPhase);

PathDashPathEffect：

Path path = new Path();  path.addCircle(0, 0, 3, Direction.CCW); PathDashPathEffect  mEffects = new PathDashPathEffect(path, 12, mPhase, PathDashPathEffect.Style.ROTATE);