CALayer的用法

 UIView *view = [[UIView alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];

    view.backgroundColor = [UIColor redColor];

    

//    设置圆角

    view.layer.cornerRadius = 10;

    view.layer.masksToBounds = YES;

    

//    .设置边框

    view.layer.borderWidth = 5;

    view.layer.borderColor = [UIColor greenColor].CGColor;

    

//    设置阴影的颜色

    view.layer.shadowColor = [UIColor darkGrayColor].CGColor;

    

    //设置阴影大小

    view.layer.shadowOffset = CGSizeMake(50, 20);

    

    //设置阴影的透明度

    view.layer.shadowOpacity = 1;

    

//    设置阴影的路径

    view.layer.shadowPath = [UIBezierPath bezierPathWithRect:CGRectMake(50, 20, 200, 200)].CGPath;

    

//    设置图片

    view.layer.contents = (__bridge id)([UIImage p_w_picpathNamed:@"p_w_picpath"].CGImage);

    [self.view addSubview:view];

    

    //本身也可以添加图片,不常用

    CALayer *layer = [[CALayer alloc] init];

    layer.frame = CGRectMake(10, 100, 300, 300);

    layer.backgroundColor = [UIColor redColor].CGColor;

    [self.view.layer addSublayer:layer];

    

    CALayer *subLayer = [[CALayer alloc] init];

    subLayer.frame = CGRectMake(10, 10, 100, 100);

    subLayer.backgroundColor = [UIColor greenColor].CGColor;

    [layer addSublayer:subLayer];