IOS: How to make a shadow for UIView on 4 side (to

问题:

I am using the code below to make the shadow for my ImageView

UIBezierPath *shadowPath = [UIBezierPath bezierPathWithRect:self.avatarImageView.bounds];
self.avatarImageView.layer.masksToBounds = NO;
self.avatarImageView.layer.shadowColor = [UIColor blackColor].CGColor;
self.avatarImageView.layer.shadowOffset = CGSizeMake(5.0f, 5.0f);
self.avatarImageView.layer.shadowOpacity = 0.8f;
self.avatarImageView.layer.shadowPath = shadowPath.CGPath;

It will drop a shadow in the right and bottom like this image.

Now I want to make my ImageView also have a shadow in top and left. What should I change in code? Is possible to make the view contains shadow in top,right,bottom,left by config in code only or I need to create other layout view for shadow? Any help would be great appreciated.

Here is what I want to achieve

Update
Thank @Dipen Panchasara for give a simple solution. Follow @Dipen Panchasara (with the shadow color is black) I will have the shadow image like this

回答1:

Like this:

float shadowSize = 10.0f;
UIBezierPath *shadowPath = [UIBezierPath bezierPathWithRect:CGRectMake(self.avatarImageView.frame.origin.x - shadowSize / 2,
                                                                       self.avatarImageView.frame.origin.y - shadowSize / 2,
                                                                       self.avatarImageView.frame.size.width + shadowSize,
                                                                       self.avatarImageView.frame.size.height + shadowSize)];
self.avatarImageView.layer.masksToBounds = NO;
self.avatarImageView.layer.shadowColor = [UIColor blackColor].CGColor;
self.avatarImageView.layer.shadowOffset = CGSizeMake(0.0f, 0.0f);
self.avatarImageView.layer.shadowOpacity = 0.8f;
self.avatarImageView.layer.shadowPath = shadowPath.CGPath;

Swift 3 version:

    let shadowSize : CGFloat = 5.0
    let shadowPath = UIBezierPath(rect: CGRect(x: -shadowSize / 2,
                                               y: -shadowSize / 2,
                                               width: self.avatarImageView.frame.size.width + shadowSize,
                                               height: self.avatarImageView.frame.size.height + shadowSize))
    self.avatarImageView.layer.masksToBounds = false
    self.avatarImageView.layer.shadowColor = UIColor.black.cgColor
    self.avatarImageView.layer.shadowOffset = CGSize(width: 0.0, height: 0.0)
    self.avatarImageView.layer.shadowOpacity = 0.5
    self.avatarImageView.layer.shadowPath = shadowPath.cgPath

回答2:

Only following code will do the job for your requirement, You don't need to create UIBezierPath for shadow path.

// *** Set masks bounds to NO to display shadow visible ***
self.avatarImageView.layer.masksToBounds = NO;
// *** Set light gray color as shown in sample ***
self.avatarImageView.layer.shadowColor = [UIColor lightGrayColor].CGColor;
// *** *** Use following to add Shadow top, left ***
self.avatarImageView.layer.shadowOffset = CGSizeMake(-5.0f, -5.0f);

// *** Use following to add Shadow bottom, right ***
//self.avatarImageView.layer.shadowOffset = CGSizeMake(5.0f, 5.0f);

// *** Use following to add Shadow top, left, bottom, right ***
// avatarImageView.layer.shadowOffset = CGSizeZero;
// avatarImageView.layer.shadowRadius = 5.0f;

// *** Set shadowOpacity to full (1) ***
self.avatarImageView.layer.shadowOpacity = 1.0f;

回答3:

Little less code for swift 3:

    view.layer.shadowColor = UIColor.black.cgColor
    view.layer.shadowOpacity = 0.7
    view.layer.shadowOffset = CGSize.zero
    view.layer.shadowRadius = 4
    view.layer.shadowPath = UIBezierPath(rect: planView.bounds).cgPath

回答4:

The best solution for shadow with a rounded corner on the same view and no need to do clipsToBounds or maskToBounds

func addShadow(cornerRadius: CGFloat, maskedCorners: CACornerMask, color: UIColor, offset: CGSize, opacity: Float, shadowRadius: CGFloat) {
        self.layer.cornerRadius = cornerRadius
        self.layer.maskedCorners = maskedCorners
        self.layer.shadowColor = color.cgColor
        self.layer.shadowOffset = offset
        self.layer.shadowOpacity = opacity
        self.layer.shadowRadius = shadowRadius
    }

回答5:

For UIView and Adding shadow, remember to set background color to the UIView.

If the background color is clearColor, no shadow appears.

回答6:

//If you’ve tried this before, you know exactly what happens. The corners will be rounded, but the shadow will be missing. If you set masksToBounds to false, the shadow will appear, but the corners will not be rounded. //to get Shadow with corner radius Add super view for container view with clear color and apply shadow for super view ,Apply corner radius for container View. try it.

   //view to apply shadow and corner radius
    containerView.layer.cornerRadius = 3
    containerView.clipsToBounds = true
    //superview of container View for to apply shadow 
    shadowView.layer.shadowOpacity = 0.1
    shadowView.layer.shadowRadius = 2.0
    shadowView.layer.masksToBounds = false
    shadowView.layer.shadowOffset = CGSize.zero

    shadowView.layer.shadowColor = UIColor.Black.cgColor

    shadowView.layer.shadowPath = UIBezierPath(roundedRect:containerView.bounds, cornerRadius: containerView.layer.cornerRadius).cgPath
    shadowView.layer.shouldRasterize = true

回答7:

CGRectInset(self.avatarImageView.bounds, -10.0, -10.0)

回答8:

**in swift 4**

  yourView.clipsToBounds = true
    yourView.layer.cornerRadius = 20
    yourView.layer.shadowPath = UIBezierPath(roundedRect: self.yourView.bounds,
                     cornerRadius: self.DeletConversation.layer.cornerRadius).cgPath
    yourView.layer.shadowColor = UIColor(hexString: "color")?.cgColor
    DeletConversation.layer.shadowOpacity = 1
    DeletConversation.layer.shadowOffset = CGSize(width: 0, height: 1.0)
    DeletConversation.layer.shadowRadius = 1
    DeletConversation.layer.masksToBounds = false

回答9:

If you are still not getting proper shadow, the problem might be the place you added the code. You should call this in viewDidLayoutSubviews when you use UIBezierPath. If you call in ViewDidLoad, you may get wrong result since the views layout process might be unfinished.

override func viewDidLayoutSubviews() {
    super.viewDidLayoutSubviews()

    //Shadow code here
}

回答10:

Without using UIBezierPath, CGSize.zero is the key here

yourView.layer.masksToBounds = false
yourView?.layer.shadowColor = UIColor.red.cgColor
yourView?.layer.shadowOffset =  CGSize.zero
yourView?.layer.shadowOpacity = 0.5
yourView?.layer.shadowRadius = 4

回答11:

There is a very detailed explanation about this here: https://www.hackingwithswift.com/example-code/uikit/how-to-add-a-shadow-to-a-uiview.

If someone is straggling with no top shadow in a collection view then this may help:

I know that this may be obvious for some people, but if you have a CollectionView with header and cell, make sure that you have space between the header and the cell, otherwise, the top shadow of the cell will be blocked by the header.

To add space, just use the insetsForSectionAt section.

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
    return UIEdgeInsets(top: 5, left: 0, bottom: 5, right: 0)

}