CALayer,,,CATextLayer,,,CAShapeLayer,, CAGradientLayer

CALayer     
    //获得根图层
    CALayer *layer = [[CALayer alloc]init]; (CATextLayer 可以填加文字)
   
    layer.backgroundColor = [UIColor blueColor].CGColor;
    layer.position = CGPointMake(ScreenWidth/2.0, ScreenHeight/2.0);
    layer.bounds = CGRectMake(0, 0, 40, 40);
    layer.cornerRadius = 40/2.0;
    layer.shadowColor=[UIColor grayColor].CGColor;
    layer.shadowOffset=CGSizeMake(2, 2);
    layer.shadowOpacity=0.9;
   layer.contents = (__bridge id)image.CGImage; //添加图片
    layer.contentsGravity = kCAGravityResizeAspect; //图片的展示方式
    
    [self.view.layer addSublayer:layer];
 
     //获取到Layer
     CALayer *layer = self.view.layer.sublayers.firstObject;
 
CATextLayer
  
    CATextLayer *lary = [CATextLayer layer];
    lary.string = @"dasfasa";
    lary.bounds = CGRectMake(0, 0, 320, 20);
    lary.font = CFBridgingRetain(@"HiraKakuProN-W3");//字体的名字 不是 UIFont
    lary.fontSize = 12.f;//字体的大小
    lary.wrapped = YES;//默认为No.  当Yes时,字符串自动适应layer的bounds大小
    lary.alignmentMode = kCAAlignmentCenter;//字体的对齐方式
    lary.position = CGPointMake(160, 410);//layer在view的位置 适用于跟随摸一个不固定长的的控件后面需要的
    lary.contentsScale = [UIScreen mainScreen].scale;//解决文字模糊 以Retina方式来渲染,防止画出来的文本像素化
    lary.foregroundColor =[UIColor redColor].CGColor;//字体的颜色 文本颜色
    [self.view.layer addSublayer:lary];
 
CAShapeLayer (对UIView进行不规则裁切, 与UIBezierPath相结合使用,)
    UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(0, 64, 100, 100)];
 
//    UIBezierPath *path = [UIBezierPath bezierPath];
//    [path moveToPoint:point1];
//    [path addLineToPoint:point2];
//    [path addLineToPoint:point3];
//    [path closePath];
//    view.layer.mask = layer;  //对View进行不规则裁切
 
    CAShapeLayer *shapeLayer = [CAShapeLayer layer];
    shapeLayer.frame = CGRectMake(0, 0, 100, 100);
    shapeLayer.strokeEnd = 0.7f;
    shapeLayer.strokeStart = 0.1f;
    shapeLayer.path = path.CGPath;
    shapeLayer.fillColor = [UIColor clearColor].CGColor;
    shapeLayer.lineWidth = 2.0f;
    shapeLayer.strokeColor = [UIColor blueColor].CGColor;
   
    [self.view.layer addSublayer:shapeLayer];
 
CAGradientLayer 渐变
 
    CAGradientLayer *gradientLayer = [CAGradientLayer layer];
    gradientLayer.frame = self.view.bounds;
    [self.view.layer addSublayer:gradientLayer];
   
    gradientLayer.colors = @[(__bridge id)[UIColor clearColor].CGColor, (__bridge id)[UIColor whiteColor].CGColor];
   
    gradientLayer.startPoint = CGPointMake(0, 0);
    gradientLayer.endPoint = CGPointMake(0, 1);
原文地址:https://www.cnblogs.com/cfl911014/p/7325651.html