UIButton bottom shadow

Question

I have a UIButton which is very similar to the standard iOS keyboard alphabet button.

I am not sure how to create a shadow only for the bottom layer like how iOS have done.

I use the below code, but I see a shadow on all the side, not just the bottom:

CALayer *buttonLayer = [[CALayer alloc] init]; buttonLayer.shadowColor = [UIColor grayColor].CGColor; buttonLayer.shadowOffset = CGSizeMake(0.f,1.f); buttonLayer.masksToBounds = NO; buttonLayer.shadowOpacity = 1.f; 

Can you please tell me how to achieve the same effect. Thanks in advance.

Answer 1

You can mix the cornerRadius and shadow properties. I tested it on iOS 8.

Objective-C:

[self.globeButton setImage:[UIImage imageNamed:@"Globe"] forState:UIControlStateNormal]; self.globeButton.backgroundColor = [UIColor colorWithRed:171 green:178 blue:186 alpha:1.0f]; // Shadow and Radius self.globeButton.layer.shadowColor = [[UIColor colorWithRed:0 green:0 blue:0 alpha:0.25f] CGColor]; self.globeButton.layer.shadowOffset = CGSizeMake(0, 2.0f); self.globeButton.layer.shadowOpacity = 1.0f; self.globeButton.layer.shadowRadius = 0.0f; self.globeButton.layer.masksToBounds = NO; self.globeButton.layer.cornerRadius = 4.0f; 

Swift:

globeButton.setImage(UIImage(named: "Globe"), for: .normal) globeButton.backgroundColor = UIColor(red: 171/255, green: 178/255, blue: 186/255, alpha: 1.0) // Shadow Color and Radius globeButton.layer.shadowColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.25).cgColor globeButton.layer.shadowOffset = CGSize(width: 0.0, height: 2.0) globeButton.layer.shadowOpacity = 1.0 globeButton.layer.shadowRadius = 0.0 globeButton.layer.masksToBounds = false globeButton.layer.cornerRadius = 4.0 

Result:

Answer 2

SWIFT 3

import UIKit  class ButtonWithShadow: UIButton {      override func draw(_ rect: CGRect) {         updateLayerProperties()     }      func updateLayerProperties() {         self.layer.shadowColor = UIColor(red: 0, green: 0, blue: 0, alpha: 0.25).cgColor         self.layer.shadowOffset = CGSize(width: 0, height: 3)         self.layer.shadowOpacity = 1.0         self.layer.shadowRadius = 10.0         self.layer.masksToBounds = false     }  } 

!! Only if you do not need corner radius and shadow simultaneously. Otherwise watch this.