iOS mask Layer 详解

CAShapeLayer 做为mask时,如何修改CAShapeLayer的边框颜色?   

path 是一个UIBezierPath,是一个多边形,
我需要显示多边形内部的东西,其余舍弃,
但我把shapeLayer作为UIImageView.layer的mask时,我设置的shapeLayer的颜色不起作用,是哪出了问题,

CAShapeLayer *shapeLayer = [CAShapeLayer layer];
    shapeLayer = [CAShapeLayer layer];
    shapeLayer.path           = path.CGPath;
    shapeLayer.strokeColor    = [UIColor redColor].CGColor;
    shapeLayer.borderColor    = [UIColor redColor].CGColor;
    shapeLayer.lineWidth      = 2;
    imageView.layer.mask = shapeLayer;
iOS 的mask layer 层：
mask是个遮罩，只有透明度信息有用，颜色信息是被忽略的，你设置它的颜色没有意义，不知道您是想实现什么功能？您如果一定要一个边框，也可以这么做试试看CAShapeLayer *shapeLayer = [CAShapeLayer layer];    shapeLayer = [CAShapeLayer layer];    shapeLayer.path           = path.CGPath;CAShapeLayer *borderLayer=[CAShapeLayer layer];    borderLayer.path    =   path.CGPath;    borderLayer.fillColor  = [UIColor clearColor].CGColor;    borderLayer.strokeColor    = [UIColor redColor].CGColor;    borderLayer.lineWidth      = 2;    borderLayer.frame=imageView.bounds;    imageView.layer.mask = shapeLayer;    [imageView.layer addSublayer:borderLayer];

参考文章：http://www.cocoachina.com/bbs/read.php?tid=295611
使用CALayer的mask属性来设置图片圆角
- (CALayer )userHeaderMask:(UIView )originalView{ CALayer * userMask = [CALayer layer]; userMask.frame = originalView.bounds; CGFloat x = originalView.frame.size.width/2; CGFloat y = originalView.frame.size.height/2; self.userMaskLayer = [CAShapeLayer layer]; self.userMaskLayer.bounds = originalView.bounds; self.userMaskLayer.path = [UIBezierPath bezierPathWithArcCenter:CGPointMake(x, y) radius:50 startAngle:0 endAngle:2*M_PI clockwise:YES].CGPath; self.userMaskLayer.position = CGPointMake(50, 50); [userMask addSublayer:self.userMaskLayer]; return userMask; }

http://www.cnblogs.com/ihojin/p/custom-shape-view.html iOS: 控制UIView的外形 #import #import @interface UIView (Shape) - (void)setShape:(CGPathRef)shape; @end #import "UIView+Shape.h" @implementation UIView (Shape) - (void)setShape:(CGPathRef)shape { if (shape == nil) { self.layer.mask = nil; } CAShapeLayer* maskLayer = [CAShapeLayer layer]; maskLayer.path = shape; self.layer.mask = maskLayer; } @end @interface UIBezierPath (BasicShape) + (UIBezierPath *)cutCorner:(CGRect)originalFrame length:(CGFloat)length; @end #import "UIBezierPath+BasicShape.h" @implementation UIBezierPath (BasicShape) + (UIBezierPath *)cutCorner:(CGRect)originalFrame length:(CGFloat)length { CGRect rect = originalFrame; UIBezierPath *bezierPath = [UIBezierPath bezierPath]; [bezierPath moveToPoint:CGPointMake(0, length)]; [bezierPath addLineToPoint:CGPointMake(length, 0)]; [bezierPath addLineToPoint:CGPointMake(rect.size.width - length, 0)]; [bezierPath addLineToPoint:CGPointMake(rect.size.width, length)]; [bezierPath addLineToPoint:CGPointMake(rect.size.width, rect.size.height - length)]; [bezierPath addLineToPoint:CGPointMake(rect.size.width - length, rect.size.height)]; [bezierPath addLineToPoint:CGPointMake(length, rect.size.height)]; [bezierPath addLineToPoint:CGPointMake(0, rect.size.height - length)]; [bezierPath closePath]; return bezierPath; } @end 在[UIView viewWillAppear:]方法中加入下面代码 [self.view setShape:[UIBezierPath cutCorner:self.view.bounds length:40].CGPath]; 效果：   ################ 让自定义 Button 响应自定义 Shape 内的点击事件 #import #import "UIView+Shape.h" #import "UIBezierPath+BasicShape.h" @interface RFButton : UIButton{ CGPathRef path; } @end // // RFButton.m // ChristApp // // Created by Haozhen Li on 13-12-6. // // #import "RFButton.h" @implementation RFButton - (id)initWithFrame:(CGRect)frame { self = [super initWithFrame:frame]; if (self) { // Initialization code } return self; } - (void)setShape:(CGPathRef)shape { [super setShape:shape]; path = shape; } - (BOOL)pointInside:(CGPoint)point withEvent:(UIEvent *)event { if (CGPathIsEmpty(path)) { return YES; } //判断触发点是否在规定的 Shape 内 if (CGPathContainsPoint(path, nil, point, nil)) { return YES; } return NO; } @end