五角大楼画一个小圆圈戴：

- (void)drawPentagon{

//(1)UIBezierPath对象

UIBezierPath *aPath = [UIBezierPath
bezierPath];

//開始点

[aPath moveToPoint:CGPointMake(100.0,
1.0)];

//划线点

[aPath addLineToPoint:CGPointMake(200.0,
40.0)];

[aPath addLineToPoint:CGPointMake(160,
140)];

[aPath addLineToPoint:CGPointMake(40.0,
140)];

[aPath addLineToPoint:CGPointMake(0.0,
40.0)];

[aPath closePath];

//设置定点是个5*5的小圆形（自己加的）

UIBezierPath *path = [UIBezierPath
bezierPathWithOvalInRect:CGRectMake(100-5/2.0,
0, 5,
5)];

[aPath appendPath:path];

//（2）加到CAShapeLayer，效果出来了

CAShapeLayer *shapelayer = [CAShapeLayer
layer];

//设置边框颜色

shapelayer.strokeColor = [[UIColor
redColor]CGColor];

//设置填充颜色

shapelayer.fillColor = [[UIColor
whiteColor]CGColor];

//就是这句话在关联彼此（UIBezierPath和CAShapeLayer）：

shapelayer.path = aPath.CGPath;

[self.view.layer
addSublayer:shapelayer];

}