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 li

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"), forState: .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.

Answer 3

To add shadow to a button with corner radius:

final class CustomButton: UIButton {

    private var shadowLayer: CAShapeLayer!

    override func layoutSubviews() {
        super.layoutSubviews()

        if shadowLayer == nil {
            shadowLayer = CAShapeLayer()
            shadowLayer.path = UIBezierPath(roundedRect: bounds, cornerRadius: 33).cgPath
            if self.backgroundColor != nil {
                shadowLayer.fillColor = self.backgroundColor?.cgColor
            }
            else{
                shadowLayer.fillColor = UIColor.white.cgColor
            }
            shadowLayer.shadowColor = UIColor.gray.cgColor
            shadowLayer.shadowPath = shadowLayer.path
            shadowLayer.shadowOffset = CGSize(width: 0.0, height: 3.0)
            shadowLayer.shadowOpacity = 0.4
            shadowLayer.shadowRadius = 2

            layer.insertSublayer(shadowLayer, at: 0)

        }

    }

}

Answer 4

Be sure to also set shadowRadius to 0:

Given a UIButton property named button set its backing layer properties like this:

self.button.layer.shadowColor = [UIColor grayColor].CGColor;
self.button.layer.shadowOffset = CGSizeMake(0, 1.0);
self.button.layer.shadowOpacity = 1.0;
self.button.layer.shadowRadius = 0.0;

Answer 5

in swift 2.0 add shadow uiview (uibutton) with code before class declaration or in swift file functions:

extension UIView {

    func addShadowView(width:CGFloat=0.2, height:CGFloat=0.2, Opacidade:Float=0.7, maskToBounds:Bool=false, radius:CGFloat=0.5){
         self.layer.shadowColor = UIColor.blackColor().CGColor
         self.layer.shadowOffset = CGSize(width: width, height: height)
         self.layer.shadowRadius = radius
         self.layer.shadowOpacity = Opacidade
         self.layer.masksToBounds = maskToBounds
    }

}

in viewdidload add this code

button.addShadowView()

Answer 6

You can try with this code: (sorry, i only know swift, not obj c. this code will add bottom shadow on your button.

button.layer.masksToBounds = false
button.layer.shadowColor = UIColor(rgb: 0x000000, alpha: 1.0).CGColor
button.layer.shadowOpacity = 1.0
button.layer.shadowRadius = 0
button.layer.shadowOffset = CGSizeMake(0, 1.0)