I’ve been working on an application for a couple of years and received a simple design request: Round the corners on a UIView and add a drop shadow.To do as given below.
I want a custom UIView... : I just wanted a blank white view with rounded corners and a light drop shadow (with no lighting effect). I can do each of those one by one but the usual clipToBounds/maskToBounds conflicts occur.
The following code snippet adds a border, border radius, and drop shadow to v, a UIView:
// border radius
[v.layer setCornerRadius:30.0f];
// border
[v.layer setBorderColor:[UIColor lightGrayColor].CGColor];
[v.layer setBorderWidth:1.5f];
// drop shadow
[v.layer setShadowColor:[UIColor blackColor].CGColor];
[v.layer setShadowOpacity:0.8];
[v.layer setShadowRadius:3.0];
[v.layer setShadowOffset:CGSizeMake(2.0, 2.0)];
Swift 5 Version :
// border radius
v.layer.cornerRadius = 30.0
// border
v.layer.borderColor = UIColor.lightGray.cgColor
v.layer.borderWidth = 1.5
// drop shadow
v.layer.shadowColor = UIColor.black.cgColor
v.layer.shadowOpacity = 0.8
v.layer.shadowRadius = 3.0
v.layer.shadowOffset = CGSize(width: 2.0, height: 2.0)
You can adjust the settings to suit your needs.
Also, add the QuartzCore framework to your project and:
#import <QuartzCore/QuartzCore.h>
See my other answer regarding masksToBounds.
Note
This may not work in all cases. If you find that this method interferes with other drawing operations that you are performing, please see this answer.
// corner radius
blueView.layer.cornerRadius = 10
// border
blueView.layer.borderWidth = 1.0
blueView.layer.borderColor = UIColor.black.cgColor
// shadow
blueView.layer.shadowColor = UIColor.black.cgColor
blueView.layer.shadowOffset = CGSize(width: 3, height: 3)
blueView.layer.shadowOpacity = 0.7
blueView.layer.shadowRadius = 4.0
What if there are sublayers or subviews (like an image) whose content we want to clip to the bounds of our view?
We can accomplish this with
blueView.layer.masksToBounds = true
(Alternatively, blueView.clipsToBounds = true gives the same result.)
But, oh no! The shadow was also clipped off because it's outside of the bounds! What to do? What to do?
Solution
Use separate views for the shadow and the border. The base view is transparent and has the shadow. The border view clips any other subcontent that it has to its borders.
// add the shadow to the base view
baseView.backgroundColor = UIColor.clear
baseView.layer.shadowColor = UIColor.black.cgColor
baseView.layer.shadowOffset = CGSize(width: 3, height: 3)
baseView.layer.shadowOpacity = 0.7
baseView.layer.shadowRadius = 4.0
// add the border to subview
let borderView = UIView()
borderView.frame = baseView.bounds
borderView.layer.cornerRadius = 10
borderView.layer.borderColor = UIColor.black.cgColor
borderView.layer.borderWidth = 1.0
borderView.layer.masksToBounds = true
baseView.addSubview(borderView)
// add any other subcontent that you want clipped
let otherSubContent = UIImageView()
otherSubContent.image = UIImage(named: "lion")
otherSubContent.frame = borderView.bounds
borderView.addSubview(otherSubContent)
This gives the following result:
Adding rounded corners and shadows can be a performance hit. You can improve performance by using a predefined path for the shadow and also specifying that it be rasterized. The following code can be added to the example above.
baseView.layer.shadowPath = UIBezierPath(roundedRect: baseView.bounds, cornerRadius: 10).cgPath
baseView.layer.shouldRasterize = true
baseView.layer.rasterizationScale = UIScreen.main.scale
See this post for more details. See here and here also.
This answer was tested with Swift 4 and Xcode 9.
Check out the example project on GitHub to make sure you use the component correctly.
Simple Swift 5 solution without any additional subviews or subclassing:
extension UIView {
func addShadow(offset: CGSize, color: UIColor, radius: CGFloat, opacity: Float) {
layer.masksToBounds = false
layer.shadowOffset = offset
layer.shadowColor = color.cgColor
layer.shadowRadius = radius
layer.shadowOpacity = opacity
let backgroundCGColor = backgroundColor?.cgColor
backgroundColor = nil
layer.backgroundColor = backgroundCGColor
}
}
Note that you should set up your view with corner radius and other properties before calling addShadow.
After that, just call this from viewDidLoad like this:
button.addShadow(offset: CGSize.init(width: 0, height: 3), color: UIColor.black, radius: 2.0, opacity: 0.35)
Final result:
Super easy and simple!
One way to do this is to put the view with rounded corners in a view with the drop shadow.
UIView* roundedView = [[UIView alloc] initWithFrame: frame];
roundedView.layer.cornerRadius = 5.0;
roundedView.layer.masksToBounds = YES;
UIView* shadowView = [[UIView alloc] initWithFrame: frame];
shadowView.layer.shadowColor = [UIColor blackColor].CGColor;
shadowView.layer.shadowRadius = 5.0;
shadowView.layer.shadowOffset = CGSizeMake(3.0, 3.0);
shadowView.layer.shadowOpacity = 1.0;
[shadowView addSubview: roundedView];
Then you can add the shadowView wherever you want.
This worked for me. Trick was to move the background color from the main view to the layer.
CALayer *layer = view.layer;
layer.cornerRadius = 15.0f;
layer.masksToBounds = NO;
layer.shadowOffset = CGSizeMake(0, 3);
layer.shadowColor = [[UIColor blackColor] CGColor];
layer.shadowRadius = 2.0f;
layer.shadowOpacity = 0.35f;
layer.shadowPath = [[UIBezierPath bezierPathWithRoundedRect:layer.bounds cornerRadius:layer.cornerRadius] CGPath];
CGColorRef bColor = view.backgroundColor.CGColor;
view.backgroundColor = nil;
layer.backgroundColor = bColor ;
I solved the problem using the following trick when assigning shadow path for the container view :
[UIBezierPath bezierPathWithRoundedRect:cell.bounds cornerRadius:12]
Notice that the path given to the shadow is a rounded rectangle with the same corner radius as the background that the cell contains:
//this is the border for the UIView that is added to a cell
cell.backgroundView.layer.cornerRadius = 12;
cell.backgroundView.layer.masksToBounds = YES;
cell.backgroundView.layer.borderColor = [UIColor darkGrayColor].CGColor;
cell.backgroundView.layer.borderWidth = 1;
//this is the shadow around the cell itself (cannot have round corners with borders and shadow, need to use two views
cell.layer.shadowRadius = 2;
cell.layer.cornerRadius = 12;
cell.layer.masksToBounds = NO;
[[cell layer] setShadowColor:[[UIColor darkGrayColor] CGColor]];
[[cell layer] setShadowOffset:CGSizeMake(0.0,0.0)];
[[cell layer] setShadowOpacity:1.0];
UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:cell.bounds cornerRadius:12];
[[cell layer] setShadowPath:[path CGPath]];
If you are struggling because of the rounded corners vs. subviews vs. masksToBounds, then try using my function:
- (UIView*)putView:(UIView*)view insideShadowWithColor:(UIColor*)color andRadius:(CGFloat)shadowRadius andOffset:(CGSize)shadowOffset andOpacity:(CGFloat)shadowOpacity
{
CGRect shadowFrame; // Modify this if needed
shadowFrame.size.width = 0.f;
shadowFrame.size.height = 0.f;
shadowFrame.origin.x = 0.f;
shadowFrame.origin.y = 0.f;
UIView * shadow = [[UIView alloc] initWithFrame:shadowFrame];
shadow.userInteractionEnabled = NO; // Modify this if needed
shadow.layer.shadowColor = color.CGColor;
shadow.layer.shadowOffset = shadowOffset;
shadow.layer.shadowRadius = shadowRadius;
shadow.layer.masksToBounds = NO;
shadow.clipsToBounds = NO;
shadow.layer.shadowOpacity = shadowOpacity;
[view.superview insertSubview:shadow belowSubview:view];
[shadow addSubview:view];
return shadow;
}
call it on your view. whether your view has rounded corners, no matter its size, its shape - a nice shadow will be drawn.
Just keep the return value of the function so you can refer to it when you want to remove the table (or for example use insertSubview:aboveView:)
Using Swift 4 and Xcode 9, this is a working example of rounding an ImageView with a drop shadow, and a border.
//set dimensions and position of image (in this case, centered)
let imageHeight: CGFloat = 150, imageWidth: CGFloat = 150
let xPosition = (self.view.frame.width / 2) - (imageWidth / 2)
let yPosition = (self.view.frame.height / 2) - (imageHeight / 2)
//set desired corner radius
let cornerRadius: CGFloat = 20
//create container for the image
let imageContainer = UIView(frame: CGRect(x: xPosition, y: yPosition, width: imageWidth, height: imageHeight))
//configure the container
imageContainer.clipsToBounds = false
imageContainer.layer.shadowColor = UIColor.black.cgColor
imageContainer.layer.shadowOpacity = 1
imageContainer.layer.shadowOffset = CGSize(width: 3.0, height: 3.0)
imageContainer.layer.shadowRadius = 5
imageContainer.layer.shadowPath = UIBezierPath(roundedRect: imageContainer.bounds, cornerRadius: cornerRadius).cgPath
//create imageView
let imageView = UIImageView(frame: imageContainer.bounds)
//configure the imageView
imageView.clipsToBounds = true
imageView.layer.cornerRadius = cornerRadius
//add a border (if required)
imageView.layer.borderColor = UIColor.black.cgColor
imageView.layer.borderWidth = 1.0
//set the image
imageView.image = UIImage(named: "bird")
//add the views to the superview
view.addSubview(imageContainer)
imageContainer.addSubview(imageView)
If you want the image to be circular: (and shown without border)
let cornerRadius = imageWidth / 2
You need to use use shadowView and roundView
shadowView
roundViewshadowView a bit inside, and its shadow needs to glow out. Adjust the insets so that shadowView is completely invisible behind roundViewroundView
The code
addSubviews(shadowView, roundView)
roundView.addSubviews(titleLabel, subtitleLabel, imageView)
// need inset
shadowView.pinEdges(view: self, inset: UIEdgeInsets(constraintInsets: 2))
roundView.pinEdges(view: self)
do {
shadowView.backgroundColor = .white // need background
let layer = shadowView.layer
layer.shadowColor = UIColor.black.cgColor
layer.shadowRadius = 3
layer.shadowOffset = CGSize(width: 3, height: 3)
layer.shadowOpacity = 0.7
layer.shouldRasterize = true
}
do {
roundView.backgroundColor = .white
let layer = roundView.layer
layer.masksToBounds = true
layer.cornerRadius = 5
}
Or you can just do below without specifying clipToBounds/maskToBounds
layer.shadowColor = UIColor.gray.cgColor
layer.shadowOffset = CGSize(width: 3, height: 3)
layer.shadowOpacity = 0.8
I've created a helper on UIView
@interface UIView (Helper)
- (void)roundCornerswithRadius:(float)cornerRadius
andShadowOffset:(float)shadowOffset;
@end
you can call it like this
[self.view roundCornerswithRadius:5 andShadowOffset:5];
Here's the implementation
- (void)roundCornerswithRadius:(float)cornerRadius
andShadowOffset:(float)shadowOffset
{
const float CORNER_RADIUS = cornerRadius;
const float SHADOW_OFFSET = shadowOffset;
const float SHADOW_OPACITY = 0.5;
const float SHADOW_RADIUS = 3.0;
UIView *superView = self.superview;
CGRect oldBackgroundFrame = self.frame;
[self removeFromSuperview];
CGRect frameForShadowView = CGRectMake(0, 0, oldBackgroundFrame.size.width, oldBackgroundFrame.size.height);
UIView *shadowView = [[UIView alloc] initWithFrame:frameForShadowView];
[shadowView.layer setShadowOpacity:SHADOW_OPACITY];
[shadowView.layer setShadowRadius:SHADOW_RADIUS];
[shadowView.layer setShadowOffset:CGSizeMake(SHADOW_OFFSET, SHADOW_OFFSET)];
[self.layer setCornerRadius:CORNER_RADIUS];
[self.layer setMasksToBounds:YES];
[shadowView addSubview:self];
[superView addSubview:shadowView];
}
Something swifty tested in swift 4
import UIKit
extension UIView {
@IBInspectable var dropShadow: Bool {
set{
if newValue {
layer.shadowColor = UIColor.black.cgColor
layer.shadowOpacity = 0.4
layer.shadowRadius = 1
layer.shadowOffset = CGSize.zero
} else {
layer.shadowColor = UIColor.clear.cgColor
layer.shadowOpacity = 0
layer.shadowRadius = 0
layer.shadowOffset = CGSize.zero
}
}
get {
return layer.shadowOpacity > 0
}
}
}
Produces
If you enable it in the Inspector like this:
It will add the User Defined Runtime Attribute, resulting in:
(I added previously the cornerRadius = 8)
:)
After one whole day research of the round corner view with shadow, I'm glad to post my custom uiview class here, hope to end this question:
#import <UIKit/UIKit.h>
@interface RoundCornerShadowView : UIView
@end
#import "RoundCornerShadowView.h"
@implementation RoundCornerShadowView
// *** must override this method, not the other method ***
// otherwise, the background corner doesn't disappear....
// @2015/05/29
-(void) layoutSubviews {
[super layoutSubviews];//is must to ensure rightly layout children view
//1. first, create Inner layer with content
CALayer *innerView = [CALayer layer];
innerView.frame = CGRectMake(0,0,self.bounds.size.width,self.bounds.size.height);
//instead of: innerView.frame = self.frame;
innerView.borderWidth = 1.0f;
innerView.cornerRadius = 6.0f;
innerView.masksToBounds = YES;
innerView.borderColor = [[UIColor lightGrayColor] CGColor];
innerView.backgroundColor = [[UIColor whiteColor] CGColor];
//put the layer to the BOTTOM of layers is also a MUST step...
//otherwise this layer will overlay the sub uiviews in current uiview...
[self.layer insertSublayer:innerView atIndex:0];
//2. then, create shadow with self layer
self.layer.masksToBounds = NO;
self.layer.shadowColor = [[UIColor darkGrayColor] CGColor];
self.layer.shadowOpacity = 0.4f;
//shadow length
self.layer.shadowRadius = 2.0f;
//no offset
self.layer.shadowOffset = CGSizeMake(0, 0);
//right down shadow
//[self.layer setShadowOffset: CGSizeMake(1.0f, 1.0f)];
//3. last but important, MUST clear current view background color, or the color will show in the corner!
self.backgroundColor = [UIColor clearColor];
}
@end
so, NO need to add subview in view or below in target view, just add one layer in current view, and do 3 step to complete it!
take a close look at to the comments in the code, it's helpful to understanding the component!
Swift 3 & IBInspectable solution:
Inspired by Ade's solution
First, create an UIView extension:
//
// UIView-Extension.swift
//
import Foundation
import UIKit
@IBDesignable
extension UIView {
// Shadow
@IBInspectable var shadow: Bool {
get {
return layer.shadowOpacity > 0.0
}
set {
if newValue == true {
self.addShadow()
}
}
}
fileprivate func addShadow(shadowColor: CGColor = UIColor.black.cgColor, shadowOffset: CGSize = CGSize(width: 3.0, height: 3.0), shadowOpacity: Float = 0.35, shadowRadius: CGFloat = 5.0) {
let layer = self.layer
layer.masksToBounds = false
layer.shadowColor = shadowColor
layer.shadowOffset = shadowOffset
layer.shadowRadius = shadowRadius
layer.shadowOpacity = shadowOpacity
layer.shadowPath = UIBezierPath(roundedRect: layer.bounds, cornerRadius: layer.cornerRadius).cgPath
let backgroundColor = self.backgroundColor?.cgColor
self.backgroundColor = nil
layer.backgroundColor = backgroundColor
}
// Corner radius
@IBInspectable var circle: Bool {
get {
return layer.cornerRadius == self.bounds.width*0.5
}
set {
if newValue == true {
self.cornerRadius = self.bounds.width*0.5
}
}
}
@IBInspectable var cornerRadius: CGFloat {
get {
return self.layer.cornerRadius
}
set {
self.layer.cornerRadius = newValue
}
}
// Borders
// Border width
@IBInspectable
public var borderWidth: CGFloat {
set {
layer.borderWidth = newValue
}
get {
return layer.borderWidth
}
}
// Border color
@IBInspectable
public var borderColor: UIColor? {
set {
layer.borderColor = newValue?.cgColor
}
get {
if let borderColor = layer.borderColor {
return UIColor(cgColor: borderColor)
}
return nil
}
}
}
Then, simply select your UIView in interface builder setting shadow ON and corner radius, like below:
The result!
Shadow + Border + Corner Radius
scrollview.backgroundColor = [UIColor whiteColor];
CALayer *ScrlViewLayer = [scrollview layer];
[ScrlViewLayer setMasksToBounds:NO ];
[ScrlViewLayer setShadowColor:[[UIColor lightGrayColor] CGColor]];
[ScrlViewLayer setShadowOpacity:1.0 ];
[ScrlViewLayer setShadowRadius:6.0 ];
[ScrlViewLayer setShadowOffset:CGSizeMake( 0 , 0 )];
[ScrlViewLayer setShouldRasterize:YES];
[ScrlViewLayer setCornerRadius:5.0];
[ScrlViewLayer setBorderColor:[UIColor lightGrayColor].CGColor];
[ScrlViewLayer setBorderWidth:1.0];
[ScrlViewLayer setShadowPath:[UIBezierPath bezierPathWithRect:scrollview.bounds].CGPath];
Here is my version in Swift 3 for a UIView
let corners:UIRectCorner = [.bottomLeft, .topRight]
let path = UIBezierPath(roundedRect: rect, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
let mask = CAShapeLayer()
mask.path = path.cgPath
mask.fillColor = UIColor.white.cgColor
let shadowLayer = CAShapeLayer()
shadowLayer.shadowColor = UIColor.black.cgColor
shadowLayer.shadowOffset = CGSize(width: 0.0, height: 4.0)
shadowLayer.shadowRadius = 6.0
shadowLayer.shadowOpacity = 0.25
shadowLayer.shadowPath = mask.path
self.layer.insertSublayer(shadowLayer, at: 0)
self.layer.insertSublayer(mask, at: 1)
Swift 4 : Create Subclass of UIView
class ShadowView: UIView {
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
// corner radius
self.layer.cornerRadius = 10
// border
self.layer.borderWidth = 1.0
self.layer.borderColor = UIColor.black.cgColor
// shadow
self.layer.shadowColor = UIColor.black.cgColor
self.layer.shadowOffset = CGSize(width: 3, height: 3)
self.layer.shadowOpacity = 0.7
self.layer.shadowRadius = 4.0
}
}
Using..
I have created UIView extension with required edges to apply shadow on as below
enum AIEdge:Int {
case
Top,
Left,
Bottom,
Right,
Top_Left,
Top_Right,
Bottom_Left,
Bottom_Right,
All,
None
}
extension UIView {
func applyShadowWithCornerRadius(color:UIColor, opacity:Float, radius: CGFloat, edge:AIEdge, shadowSpace:CGFloat, cornerRadius: CGFloat) {
var sizeOffset:CGSize = CGSize.zero
switch edge {
case .Top:
sizeOffset = CGSize(width: 0, height: -shadowSpace)
case .Left:
sizeOffset = CGSize(width: -shadowSpace, height: 0)
case .Bottom:
sizeOffset = CGSize(width: 0, height: shadowSpace)
case .Right:
sizeOffset = CGSize(width: shadowSpace, height: 0)
case .Top_Left:
sizeOffset = CGSize(width: -shadowSpace, height: -shadowSpace)
case .Top_Right:
sizeOffset = CGSize(width: shadowSpace, height: -shadowSpace)
case .Bottom_Left:
sizeOffset = CGSize(width: -shadowSpace, height: shadowSpace)
case .Bottom_Right:
sizeOffset = CGSize(width: shadowSpace, height: shadowSpace)
case .All:
sizeOffset = CGSize(width: 0, height: 0)
case .None:
sizeOffset = CGSize.zero
}
self.layer.cornerRadius = cornerRadius
self.layer.masksToBounds = true
self.layer.shadowColor = color.cgColor
self.layer.shadowOpacity = opacity
self.layer.shadowOffset = sizeOffset
self.layer.shadowRadius = radius
self.layer.masksToBounds = false
self.layer.shadowPath = UIBezierPath(roundedRect:self.bounds, cornerRadius:self.layer.cornerRadius).cgPath
}
}
Finally, you can call the shadow function as below for any of your UIView subclass, you can also specify the edge to apply shadow on, try different variations as per your need changing parameters of below method call.
viewRoundedToBeShadowedAsWell.applyShadowWithCornerRadius(color: .gray, opacity: 1, radius: 15, edge: AIEdge.All, shadowSpace: 15)
NOTE: If still that doesn't work, try calling it from MAIN THREAD
DispatchQueue.main.async {
viewRoundedToBeShadowedAsWell.applyShadowWithCornerRadius(color: .gray, opacity: 1, radius: 15, edge: AIEdge.All, shadowSpace: 15)
}
Hope someone finds this useful !
Below is the result images:
Well if you don't want to change your nibs and view hierarchy as suggested David C. this method will do it for you. To add rounded corners and shadow to your UIImageView just use this method, for example:
[Utils roundCornersForImageView:myImageView withCornerRadius:6.0
andShadowOffset:2.0];
(!) For performance reasons I don't think it is a good idea to use this code in something like UITableView, since this code changes view hierarchy. So I will suggest to change your nib and add a container view for shadow effect and use Davic C. code.
+ (void)roundCornersForImageView:(UIImageView *)imageView
withCornerRadius:(float)cornerRadius andShadowOffset:(float)shadowOffset
{
const float CORNER_RADIUS = cornerRadius;
const float BORDER_WIDTH = 1.0;
const float SHADOW_OFFSET = shadowOffset;
const float SHADOW_OPACITY = 0.8;
const float SHADOW_RADIUS = 3.0;
//Our old image now is just background image view with shadow
UIImageView *backgroundImageView = imageView;
UIView *superView = backgroundImageView.superview;
//Make wider actual visible rect taking into account shadow
//offset
CGRect oldBackgroundFrame = backgroundImageView.frame;
CGRect newBackgroundFrame = CGRectMake(oldBackgroundFrame.origin.x, oldBackgroundFrame.origin.y, oldBackgroundFrame.size.width + SHADOW_OFFSET, oldBackgroundFrame.size.height + SHADOW_OFFSET);
[backgroundImageView removeFromSuperview];
backgroundImageView.frame = newBackgroundFrame;
//Make new UIImageView with rounded corners and put our old image
CGRect frameForRoundedImageView = CGRectMake(0, 0, oldBackgroundFrame.size.width, oldBackgroundFrame.size.height);
UIImageView *roundedImageView = [[UIImageView alloc]initWithFrame:frameForRoundedImageView];
roundedImageView.image = imageView.image;
[roundedImageView.layer setCornerRadius:CORNER_RADIUS];
[roundedImageView.layer setBorderColor:[UIColor lightGrayColor].CGColor];
[roundedImageView.layer setBorderWidth:BORDER_WIDTH];
[roundedImageView.layer setMasksToBounds:YES];
//Set shadow preferences
[backgroundImageView setImage:nil];
[backgroundImageView.layer setShadowColor:[UIColor blackColor].CGColor];
[backgroundImageView.layer setShadowOpacity:SHADOW_OPACITY];
[backgroundImageView.layer setShadowRadius:SHADOW_RADIUS];
[backgroundImageView.layer setShadowOffset:CGSizeMake(SHADOW_OFFSET, SHADOW_OFFSET)];
//Add out two image views back to the view hierarchy.
[backgroundImageView addSubview:roundedImageView];
[superView addSubview:backgroundImageView];
}
Old thread still current...
I've edited Daniel Gindi's method to make it possible to use it with buttons etc. as well. If anyone needs rounded corners or wants to combine round corners and a border it has to be set on the view's layer which is passed to this method. I've also set the rasterization to speed it up a little.
+ (UIView*)putView:(UIView*)view insideShadowWithColor:(CGColorRef)color
andRadius:(CGFloat)shadowRadius
andOffset:(CGSize)shadowOffset
andOpacity:(CGFloat)shadowOpacity
{
// Must have same position like "view"
UIView *shadow = [[UIView alloc] initWithFrame:view.frame];
shadow.layer.contentsScale = [UIScreen mainScreen].scale;
shadow.userInteractionEnabled = YES; // Modify this if needed
shadow.layer.shadowColor = color;
shadow.layer.shadowOffset = shadowOffset;
shadow.layer.shadowRadius = shadowRadius;
shadow.layer.masksToBounds = NO;
shadow.clipsToBounds = NO;
shadow.layer.shadowOpacity = shadowOpacity;
shadow.layer.rasterizationScale = [UIScreen mainScreen].scale;
shadow.layer.shouldRasterize = YES;
[view.superview insertSubview:shadow belowSubview:view];
[shadow addSubview:view];
// Move view to the top left corner inside the shadowview
// ---> Buttons etc are working again :)
view.frame = CGRectMake(0, 0, view.frame.size.width, view.frame.size.height);
return shadow;
}
The following worked best for me (this code lies in UIView extension, so self denotes some UIView to which we must add a shadow and round corner)
- (void)addShadowViewWithCornerRadius:(CGFloat)radius {
UIView *container = self.superview;
if (!container) {
return;
}
UIView *shadowView = [[UIView alloc] init];
shadowView.translatesAutoresizingMaskIntoConstraints = NO;
shadowView.backgroundColor = [UIColor lightGrayColor];
shadowView.layer.cornerRadius = radius;
shadowView.layer.masksToBounds = YES;
[container addSubview:shadowView];
[container bringSubviewToFront:shadowView];
[container addConstraint:[NSLayoutConstraint constraintWithItem:shadowView
attribute:NSLayoutAttributeWidth
relatedBy:NSLayoutRelationEqual
toItem:self
attribute:NSLayoutAttributeWidth
multiplier:1.0
constant:0.0]];
[container addConstraint:[NSLayoutConstraint constraintWithItem:shadowView
attribute:NSLayoutAttributeLeading
relatedBy:NSLayoutRelationEqual
toItem:self
attribute:NSLayoutAttributeLeading
multiplier:1.0
constant:2.0]];
[container addConstraint:[NSLayoutConstraint constraintWithItem:shadowView
attribute:NSLayoutAttributeHeight
relatedBy:NSLayoutRelationEqual
toItem:self
attribute:NSLayoutAttributeHeight
multiplier:1.0
constant:0.0]];
[container addConstraint:[NSLayoutConstraint constraintWithItem:shadowView
attribute:NSLayoutAttributeTop
relatedBy:NSLayoutRelationEqual
toItem:self
attribute:NSLayoutAttributeTop
multiplier:1.0
constant:2.0]];
[container sendSubviewToBack:shadowView];
}
The main difference between this and other code samples is that this adds the shadow view as a sibling view (as against adding the current view as subview of shadow view), thereby eliminating the need to modify the existing view hierarchy in any way.
Swift 4 Solution for making UICollectionViewCell round and adding Shadows, without any extensions and complications :)
Note: For simple views e.g Buttons. See the @suragch's Answer in this post. https://stackoverflow.com/a/34984063/7698092. Tested successfully for buttons
In case if any one still struggling to round the corners and add shadows at the same time. Although this solution works with UICollectionViewCell, it can be generalized to any view.
This technique worked for me without making any extensions and all the complicated stuff. I am working with storyBoard.
Technique
You must add a UIView (lets say it "containerView") inside your UICollectionViewCell in storyBoard and add all the required views (buttons, images etc) inside this containerView.
See the Screenshot. 
Connect the outlet for containerView. Add following lines of code in CellforItemAtIndexPath delegate function.
//adds shadow to the layer of cell
cell.layer.cornerRadius = 3.0
cell.layer.masksToBounds = false
cell.layer.shadowColor = UIColor.black.cgColor
cell.layer.shadowOffset = CGSize(width: 0, height: 0)
cell.layer.shadowOpacity = 0.6
//makes the cell round
let containerView = cell.containerView!
containerView.layer.cornerRadius = 8
containerView.clipsToBounds = true
Output
See the simulator Screenshot 
daniel.gindi's answer above did the trick for me! (+1 daniel) However, I had to make minor adjustments - change the shadowFrame size to be same as view's frame size, and enable user interaction. Here's the updated code:
+ (UIView*)putView:(UIView*)view insideShadowWithColor:(UIColor*)color andRadius:(CGFloat)shadowRadius andOffset:(CGSize)shadowOffset andOpacity:(CGFloat)shadowOpacity
{
CGRect shadowFrame; // Modify this if needed
// Modified this line
shadowFrame.size = CGSizeMake(view.frame.size.width, view.frame.size.height);
shadowFrame.origin.x = 0.f;
shadowFrame.origin.y = 0.f;
UIView * shadow = [[UIView alloc] initWithFrame:shadowFrame];
// Modified this line
shadow.userInteractionEnabled = YES;
shadow.layer.shadowColor = color.CGColor;
shadow.layer.shadowOffset = shadowOffset;
shadow.layer.shadowRadius = shadowRadius;
shadow.layer.masksToBounds = NO;
shadow.clipsToBounds = NO;
shadow.layer.shadowOpacity = shadowOpacity;
[shadow addSubview:view];
return shadow;
}
I would like to add that in my case, I was trying to add this to a 3rd party view controller, i.e. I did not have direct control over the code. So, here's how I used the function above:
UIView *shadow = [self putView:vc.view
insideShadowWithColor:[UIColor blackColor]
andRadius:5.0
andOffset:CGSizeMake(0.0, 0.0)
andOpacity:1.0];
vc.view = shadow;
vc.view.layer.cornerRadius = 5.0;
vc.view.layer.masksToBounds = YES;
I make some changes to the code of daniel.gindi
This is all you need to make it work.
+ (void)putView:(UIView*)view insideShadowWithColor:(UIColor*)color andBlur: (CGFloat)blur andOffset:(CGSize)shadowOffset andOpacity:(CGFloat)shadowOpacity
{
CGRect shadowFrame = view.frame;
UIView * shadow = [[UIView alloc] initWithFrame:shadowFrame];
shadow.backgroundColor = [UIColor redColor];
shadow.userInteractionEnabled = YES; // Modify this if needed
shadow.layer.shadowColor = color.CGColor;
shadow.layer.shadowOffset = shadowOffset;
shadow.layer.shadowRadius = blur;
shadow.layer.cornerRadius = view.layer.cornerRadius;
shadow.layer.masksToBounds = NO;
shadow.clipsToBounds = NO;
shadow.layer.shadowOpacity = shadowOpacity;
[view.superview insertSubview:shadow belowSubview:view];
}
You need to use two UIViews to achieve this. One UIView will work like shadow and other one will work for rounded border.
Here is a code snippet a Class Method with a help of a protocol:
@implementation UIMethods
+ (UIView *)genComposeButton:(UIViewController <UIComposeButtonDelegate> *)observer;
{
UIView *shadow = [[UIView alloc]init];
shadow.layer.cornerRadius = 5.0;
shadow.layer.shadowColor = [[UIColor blackColor] CGColor];
shadow.layer.shadowOpacity = 1.0;
shadow.layer.shadowRadius = 10.0;
shadow.layer.shadowOffset = CGSizeMake(0.0f, -0.5f);
UIButton *btnCompose = [[UIButton alloc]initWithFrame:CGRectMake(0, 0,60, 60)];
[btnCompose setUserInteractionEnabled:YES];
btnCompose.layer.cornerRadius = 30;
btnCompose.layer.masksToBounds = YES;
[btnCompose setImage:[UIImage imageNamed:@"60x60"] forState:UIControlStateNormal];
[btnCompose addTarget:observer action:@selector(btnCompose_click:) forControlEvents:UIControlEventTouchUpInside];
[shadow addSubview:btnCompose];
return shadow;
}
In the code above btnCompose_click: will become a @required delegate method which will fire on the button click.
And here I added a button to my UIViewController like this:
UIView *btnCompose = [UIMethods genComposeButton:self];
btnCompose.frame = CGRectMake(self.view.frame.size.width - 75,
self.view.frame.size.height - 75,
60, 60);
[self.view addSubview:btnCompose];
The result will look like this:
I have tried so many solutions from this post and ended up with the below solution. This is full proof solution unless you need to drop shadow on a clear color view.
- (void)addShadowWithRadius:(CGFloat)shadowRadius withOpacity:(CGFloat)shadowOpacity withOffset:(CGSize)shadowOffset withColor:(UIColor *)shadowColor withCornerradius:(CGFloat)cornerRadius
{
UIView *viewShadow = [[UIView alloc]initWithFrame:self.frame];
viewShadow.backgroundColor = [UIColor whiteColor];
viewShadow.layer.shadowColor = shadowColor.CGColor;
viewShadow.layer.shadowOffset = shadowOffset;
viewShadow.layer.shadowRadius = shadowRadius;
viewShadow.layer.shadowOpacity = shadowOpacity;
viewShadow.layer.cornerRadius = cornerRadius;
viewShadow.layer.masksToBounds = NO;
[self.superview insertSubview:viewShadow belowSubview:self];
[viewShadow setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.superview addConstraint:[NSLayoutConstraint constraintWithItem:viewShadow attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationEqual toItem:self attribute:NSLayoutAttributeWidth multiplier:1.0 constant:0]];
[self.superview addConstraint:[NSLayoutConstraint constraintWithItem:viewShadow attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:self attribute:NSLayoutAttributeHeight multiplier:1.0 constant:0]];
[self.superview addConstraint:[NSLayoutConstraint constraintWithItem:viewShadow attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:viewShadow attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0]];
[self.superview addConstraint:[NSLayoutConstraint constraintWithItem:viewShadow attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:viewShadow attribute:NSLayoutAttributeCenterY multiplier:1.0 constant:0]];
[self layoutIfNeeded];
self.layer.cornerRadius = cornerRadius;
self.layer.masksToBounds = YES;
}
import UIKit
extension UIView {
func addShadow(shadowColor: UIColor, offSet: CGSize, opacity: Float, shadowRadius: CGFloat, cornerRadius: CGFloat, corners: UIRectCorner, fillColor: UIColor = .white) {
let shadowLayer = CAShapeLayer()
let size = CGSize(width: cornerRadius, height: cornerRadius)
let cgPath = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: corners, cornerRadii: size).cgPath //1
shadowLayer.path = cgPath //2
shadowLayer.fillColor = fillColor.cgColor //3
shadowLayer.shadowColor = shadowColor.cgColor //4
shadowLayer.shadowPath = cgPath
shadowLayer.shadowOffset = offSet //5
shadowLayer.shadowOpacity = opacity
shadowLayer.shadowRadius = shadowRadius
self.layer.addSublayer(shadowLayer)
}
}
This is how you do it, with rounded corners and rounded shadows without bothering with paths.
//Inner view with content
[imageView.layer setBorderColor:[[UIColor lightGrayColor] CGColor]];
[imageView.layer setBorderWidth:1.0f];
[imageView.layer setCornerRadius:8.0f];
[imageView.layer setMasksToBounds:YES];
//Outer view with shadow
UIView* shadowContainer = [[UIView alloc] initWithFrame:imageView.frame];
[shadowContainer.layer setMasksToBounds:NO];
[shadowContainer.layer setShadowColor:[[UIColor blackColor] CGColor]];
[shadowContainer.layer setShadowOpacity:0.6f];
[shadowContainer.layer setShadowRadius:2.0f];
[shadowContainer.layer setShadowOffset: CGSizeMake(0.0f, 2.0f)];
[shadowContainer addSubview:imageView];
The view with content, in my case a UIImageView, has a corner radius and therefore has to mask to bounds.
We create another equally sized view for the shadows, set it's maskToBounds to NO and then add the content view to the container view (e.g. shadowContainer).
I write this UIView category method to solve this problem, uses separate views for the shadow and the corner radius.
-(UIView *)shadowedWrapViewWithBounds:(CGRect)bounds {
UIView *baseView = [[UIView alloc] init];
baseView.bounds = bounds;
baseView.backgroundColor = [UIColor clearColor];
baseView.layer.shadowColor = [UIColor blackColor].CGColor;
baseView.layer.shadowOffset = CGSizeMake(0, 0);
baseView.layer.shadowOpacity = 0.7;
baseView.layer.shadowRadius = 4.0;
// improve performance
baseView.layer.shadowPath = [UIBezierPath bezierPathWithRoundedRect:baseView.bounds cornerRadius:4].CGPath;
baseView.layer.shouldRasterize = YES;
baseView.layer.rasterizationScale = [UIScreen mainScreen].scale;
[baseView addSubview:self];
//use Masonry autolayout, self can set corner radius
[self makeConstraints:^(MASConstraintMaker *make) {
make.edges.equalTo(baseView);
}];
return baseView;
}
