iOS UIView 添加阴影

 
#pragma mark - 添加阴影效果
- (void)addShadowToView:(UIView *)theView withColor:(UIColor *)theColor {

    theView.layer.masksToBounds = NO;
    // 阴影颜色
    theView.layer.shadowColor = theColor.CGColor;
    // 阴影偏移，默认(0, -3)
    theView.layer.shadowOffset = CGSizeMake(0,0);
    // 阴影透明度，默认0
    theView.layer.shadowOpacity = 0.5;
    // 阴影半径，默认3
    theView.layer.shadowRadius = 5;
}

添加单边阴影效果
- (void)addShadowToView:(UIView *)theView withColor:(UIColor *)theColor {

    theView.layer.masksToBounds = NO;
    theView.layer.shadowColor = theColor.CGColor;
    theView.layer.shadowOffset = CGSizeMake(0,0);
    theView.layer.shadowOpacity = 0.5;
    theView.layer.shadowRadius = 5;
    // 单边阴影 顶边
    float shadowPathWidth = theView.layer.shadowRadius;
    CGRect shadowRect = CGRectMake(0, 0-shadowPathWidth/2.0, theView.bounds.size.width, shadowPathWidth);
    UIBezierPath *path = [UIBezierPath bezierPathWithRect:shadowRect];
    theView.layer.shadowPath = path.CGPath;
}