Swift PageViewController gradient background - ios

I have a PageViewController and need to set a gradient background to it.
When using gradient background in normal ViewControllers, I use the following:
let layer = self.layer as! CAGradientLayer
layer.colors = [FirstColor.cgColor, SecondColor.cgColor]
layer.locations = [0.5]
when I try to use self.view.layer inside my PageViewController I get an error:
Could not cast value of type 'CALayer' (0x104f57900) to 'CAGradientLayer'
Can someone help me setting the background of a page view controller to an gradient?
Thanks

Hi you can create a UIView extension and just call like this:
view.applyGradient(colours: [UIColor.red, UIColor.green])
here the extension code
extension UIView {
func applyGradient(colours: [UIColor]) -> Void {
clipsToBounds = true
let gradient: CAGradientLayer = CAGradientLayer()
gradient.frame = self.bounds
gradient.colors = colours.map { $0.cgColor }
gradient.startPoint = CGPoint(x: 0, y: 0)
gradient.endPoint = CGPoint(x: 1, y: 0)
layer.insertSublayer(gradient, at: 0)
}
}
with this code you can apply to UIButtons, UILabels, anything that extends from UIView
hope it helps

Related

Change Gradient Background of UIView Through Sublayer

I've got this function defined in an extension of UIView which I use to set the gradient background on a UIView:
func setGradientBackground(colorTop: UIColor, colorBottom: UIColor, withCornerRadius : CGFloat){
let gradientLayer = CAGradientLayer()
gradientLayer.colors = [colorBottom.cgColor, colorTop.cgColor]
gradientLayer.startPoint = CGPoint(x: 0.5, y: 1.0)
gradientLayer.endPoint = CGPoint(x: 0.5, y: 0.0)
gradientLayer.locations = [0, 1]
gradientLayer.frame = bounds
gradientLayer.cornerRadius = withCornerRadius
layer.insertSublayer(gradientLayer, at: 0)
}
It is used as follows:
view.setGradientBackground(colorTop: UIColor.blue, colorBottom: UIColor.red, withCornerRadius: 10)
The problem is, if I have already called this function once on a view, the second time I call it, it does not do anything. I suspect this is caused by the subLayer persisting from the previous insertion.
I've tried adding:
if layer.sublayers?.count ?? 0 > 0 {
layer.sublayers?.remove(at: 0)
}
to the top of that function, but that causes by code to crash with a BAD_INSTRUCTION exception.
You can get the Gradient layer and can remove from view anywhere you want to ... Not just by adding it again you remove it..
if let gradientLayer = (yourView.layer.sublayers?.compactMap { $0 as? CAGradientLayer })?.first {
print("gradientLayer is presnet")
gradientLayer.removeFromSuperlayer()
} else {
print("its not added on layer yet")
}
The easiest option would be to check to see if the layer's sublayer is a gradient layer. This isn't perfectly safe because if you happen to have another gradient layer at index 0 of the sublayers, it will change the incorrect sublayer.
func setGradientBackground(colorTop: UIColor, colorBottom: UIColor, withCornerRadius cornerRadius: CGFloat) {
let gradientLayer = layer.sublayers?.first as? CAGradientLayer ?? CAGradientLayer()
// The rest of your existing layer customization code here
guard gradientLayer.superlayer != self else {
return
}
layer.sublayers?.insertSublayer(gradientLayer, at: 0)
}

Creating a clear button with gradient border and gradient text

I'm trying to add a gradient to my UIButton Title and to the border of the button. I've gone through most of the solution on here which I cannot get working for the life of me, might be outdated, I'm not sure. So currently I extend the UIView in order to set the gradient of whatever. So how would I add another function for this feature?
func setGradientBackground(colorOne: UIColor, colorTwo: UIColor) {
let gradientlayer = CAGradientLayer()
gradientlayer.frame = bounds
gradientlayer.colors = [colorOne.cgColor, colorTwo.cgColor]
gradientlayer.locations = [0, 1]
gradientlayer.startPoint = CGPoint(x: 1.0, y: 0.0)
gradientlayer.endPoint = CGPoint(x: 0.0, y: 0.0)
layer.insertSublayer(gradientlayer, at: 0)
}
I have created a demo for you, you can do this with the help of CAGradientLayer see the following output and code for this.
Storyboard:
For gradient button text color and border put your UIButton inside UIView, then assign CAGradientLayer to UIview.
Note:- Don't forget to set the button as the views mask, See the following code.
import UIKit
class ViewController: UIViewController {
#IBOutlet var viewForButton: UIView!
#IBOutlet var myButton: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
// Create a gradient layer
let gradient = CAGradientLayer()
// gradient colors in order which they will visually appear
gradient.colors = [UIColor.red.cgColor, UIColor.blue.cgColor]
// Gradient from left to right
gradient.startPoint = CGPoint(x: 0.0, y: 0.5)
gradient.endPoint = CGPoint(x: 1.0, y: 0.5)
// set the gradient layer to the same size as the view
gradient.frame = viewForButton.bounds
// add the gradient layer to the views layer for rendering
viewForButton.layer.insertSublayer(gradient, at: 0)
// Tha magic! Set the button as the views mask
viewForButton.mask = myButton
//Set corner Radius and border Width of button
myButton.layer.cornerRadius = myButton.frame.size.height / 2
myButton.layer.borderWidth = 5.0
}
}
Extension: You can also prefer this extension for the same.
extension UIView{
func gradientButton(_ buttonText:String, startColor:UIColor, endColor:UIColor) {
let button:UIButton = UIButton(frame: self.bounds)
button.setTitle(buttonText, for: .normal)
let gradient = CAGradientLayer()
gradient.colors = [startColor.cgColor, endColor.cgColor]
gradient.startPoint = CGPoint(x: 0.0, y: 0.5)
gradient.endPoint = CGPoint(x: 1.0, y: 0.5)
gradient.frame = self.bounds
self.layer.insertSublayer(gradient, at: 0)
self.mask = button
button.layer.cornerRadius = button.frame.size.height / 2
button.layer.borderWidth = 5.0
}
}
How to use:
testView.gradientButton("Hello", startColor: .red, endColor: .blue)
You just need to add below UIView extension and call the function to get desire gradient button,
func covertToGradientButtonWith(title: String, radius: CGFloat, borderWidth: CGFloat, gradientStartColor: UIColor, gradientEndColor: UIColor) {
let button:UIButton = UIButton(frame: self.bounds)
button.setTitle(title, for: .normal)
let gradient = CAGradientLayer()
gradient.colors = [gradientStartColor.cgColor, gradientEndColor.cgColor]
gradient.startPoint = CGPoint(x: 0.0, y: 0.5)
gradient.endPoint = CGPoint(x: 1.0, y: 0.5)
gradient.frame = self.bounds
self.layer.insertSublayer(gradient, at: 0)
self.mask = button
button.layer.cornerRadius = radius
button.layer.borderWidth = borderWidth
}
Hope, this solution may help you.

How to add gradient layer which fills the view frame exactly

In my app i'm adding the gradient layer to UIView and UIToolBar but it doesn't fill the views exactly
let gradient:CAGradientLayer = CAGradientLayer()
gradient.frame = self.vw_gradientForToolBar.bounds
gradient.colors = [hexStringToUIColor(hex: "#5d8f32").cgColor,hexStringToUIColor(hex: "#04667f").cgColor]
gradient.startPoint = CGPoint(x: 0, y: 0)
gradient.endPoint = CGPoint(x: 0.5, y: 0)
UIGraphicsBeginImageContextWithOptions(CGSize(width: 1, height: 1), false, 0.0)
let img : UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
self.toolBar.setBackgroundImage(img, forToolbarPosition: .any, barMetrics: .default)
vw_gradientForToolBar.layer.addSublayer(gradient)
View Hirarchy
enter image description here
It's a little tough to tell exactly what you have going on, based on the images you posted, however... This may simplify things for you.
First, keep in mind that Layers do not auto-scale, so when your tool bar changes size (different devices, device rotation, etc), you want your gradient layer to also resize. Best way to do that is to use a UIView subclass and override layoutSubviews().
So, add this class to your code:
class GradientView: UIView {
override class var layerClass: AnyClass {
return CAGradientLayer.self
}
override func layoutSubviews() {
let gradientLayer = layer as! CAGradientLayer
gradient.colors = [hexStringToUIColor(hex: "#5d8f32").cgColor,hexStringToUIColor(hex: "#04667f").cgColor]
gradientLayer.startPoint = CGPoint(x: 0, y: 0)
gradientLayer.endPoint = CGPoint(x: 0.5, y: 0)
}
}
Then in your controller's viewDidLoad() function:
override func viewDidLoad() {
super.viewDidLoad()
let vwGrad = GradientView()
vwGrad.frame = toolBar.frame
vwGrad.autoresizingMask = [.flexibleWidth, .flexibleHeight]
self.toolBar.insertSubview(vwGrad, at: 0)
}
Note: you would no longer need your vw_gradientForToolBar (which, I'm assuming, is a UIView connected via #IBOutlet).

How to add gradient to UIView as an extension

I am trying to add some gradient to a view in Xcode and for simplicity I tried to add my method as an extension to UIView:
extension UIView {
func applyGradient() {
let gradient = CAGradientLayer()
gradient.colors = [UIColor(hex: "F5FF8C").cgColor,
UIColor(hex: "F1F99D").cgColor,
UIColor(hex: "FDFFE0").cgColor]
gradient.locations = [0.0, 0.5, 1.0]
self.layer.insertSublayer(gradient, at: 0)
}
}
But apparently this doesn't work when I call it in my viewDidLoad:
self.myView.applyGradient()
Can someone point to me what am I doing wrong ?
In the question, you haven't set the frame at all. In the comment, your frame was not set correctly. This is the code that should work properly:
extension UIView {
func applyGradient() {
let gradient = CAGradientLayer()
gradient.colors = [UIColor.red.cgColor,
UIColor.green.cgColor,
UIColor.black.cgColor] // your colors go here
gradient.locations = [0.0, 0.5, 1.0]
gradient.frame = self.bounds
self.layer.insertSublayer(gradient, at: 0)
}
}
With your code:
With the modified code:
Explanation
gradient.frame.size = self.frame.size doesn't work, while gradient.frame = self.bounds does, because the frame attribute contains both the location and the size of the view, and even if you set the gradient's frame size, you do not specify the location of the gradient... So the gradient is never actually added to the view. By setting the frame attribute directly to the bounds of the view, you also add the location of the gradient in the view.

Programmatically create a UIView with color gradient

I'm trying to generate a view with a gradient color background (A solid color to transparent) at runtime. Is there a way of doing that?
Objective-C:
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 50)];
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = view.bounds;
gradient.colors = #[(id)[UIColor whiteColor].CGColor, (id)[UIColor blackColor].CGColor];
[view.layer insertSublayer:gradient atIndex:0];
Swift:
let view = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 50))
let gradient = CAGradientLayer()
gradient.frame = view.bounds
gradient.colors = [UIColor.white.cgColor, UIColor.black.cgColor]
view.layer.insertSublayer(gradient, at: 0)
Info: use startPoint and endPoint to change direction of gradient.
If there are any other views added onto this UIView (such as a UILabel), you may want to consider setting the background color of those UIView’s to [UIColor clearColor] so the gradient view is presented instead of the background color for sub views. Using clearColor has a slight performance hit.
You can create a custom class GradientView:
Swift 5
class GradientView: UIView {
override open class var layerClass: AnyClass {
return CAGradientLayer.classForCoder()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
let gradientLayer = layer as! CAGradientLayer
gradientLayer.colors = [UIColor.white.cgColor, UIColor.black.cgColor]
}
}
In the storyboard, set the class type to any view that you want to have gradient background:
This is better in the following ways:
No need to set frame of CLayer
Use NSConstraint as usual on the UIView
Don't need to create sublayers (less memory use)
Try This it worked like a charm for me,
Objective C
I have set RGB gradient background Color to UIview
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0,0,320,35)];
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = view.bounds;
gradient.startPoint = CGPointZero;
gradient.endPoint = CGPointMake(1, 1);
gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor colorWithRed:34.0/255.0 green:211/255.0 blue:198/255.0 alpha:1.0] CGColor],(id)[[UIColor colorWithRed:145/255.0 green:72.0/255.0 blue:203/255.0 alpha:1.0] CGColor], nil];
[view.layer addSublayer:gradient];
UPDATED :-
Swift3 +
Code :-
var gradientView = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 35))
let gradientLayer:CAGradientLayer = CAGradientLayer()
gradientLayer.frame.size = self.gradientView.frame.size
gradientLayer.colors =
[UIColor.white.cgColor,UIColor.red.withAlphaComponent(1).cgColor]
//Use diffrent colors
gradientView.layer.addSublayer(gradientLayer)
You can add starting and end point of gradient color.
gradientLayer.startPoint = CGPoint(x: 0.0, y: 1.0)
gradientLayer.endPoint = CGPoint(x: 1.0, y: 1.0)
For more details description refer CAGradientLayer Doc
Hope this is help for some one .
This is my recommended approach.
To promote reusability, I'd say create a category of CAGradientLayer and add your desired gradients as class methods. Specify them in the header file like this :
#import <QuartzCore/QuartzCore.h>
#interface CAGradientLayer (SJSGradients)
+ (CAGradientLayer *)redGradientLayer;
+ (CAGradientLayer *)blueGradientLayer;
+ (CAGradientLayer *)turquoiseGradientLayer;
+ (CAGradientLayer *)flavescentGradientLayer;
+ (CAGradientLayer *)whiteGradientLayer;
+ (CAGradientLayer *)chocolateGradientLayer;
+ (CAGradientLayer *)tangerineGradientLayer;
+ (CAGradientLayer *)pastelBlueGradientLayer;
+ (CAGradientLayer *)yellowGradientLayer;
+ (CAGradientLayer *)purpleGradientLayer;
+ (CAGradientLayer *)greenGradientLayer;
#end
Then in your implementation file, specify each gradient with this syntax :
+ (CAGradientLayer *)flavescentGradientLayer
{
UIColor *topColor = [UIColor colorWithRed:1 green:0.92 blue:0.56 alpha:1];
UIColor *bottomColor = [UIColor colorWithRed:0.18 green:0.18 blue:0.18 alpha:1];
NSArray *gradientColors = [NSArray arrayWithObjects:(id)topColor.CGColor, (id)bottomColor.CGColor, nil];
NSArray *gradientLocations = [NSArray arrayWithObjects:[NSNumber numberWithInt:0.0],[NSNumber numberWithInt:1.0], nil];
CAGradientLayer *gradientLayer = [CAGradientLayer layer];
gradientLayer.colors = gradientColors;
gradientLayer.locations = gradientLocations;
return gradientLayer;
}
Then simply import this category in your ViewController or any other required subclass, and use it like this :
CAGradientLayer *backgroundLayer = [CAGradientLayer purpleGradientLayer];
backgroundLayer.frame = self.view.frame;
[self.view.layer insertSublayer:backgroundLayer atIndex:0];
extension UIView {
func applyGradient(isVertical: Bool, colorArray: [UIColor]) {
layer.sublayers?.filter({ $0 is CAGradientLayer }).forEach({ $0.removeFromSuperlayer() })
let gradientLayer = CAGradientLayer()
gradientLayer.colors = colorArray.map({ $0.cgColor })
if isVertical {
//top to bottom
gradientLayer.locations = [0.0, 1.0]
} else {
//left to right
gradientLayer.startPoint = CGPoint(x: 0.0, y: 0.5)
gradientLayer.endPoint = CGPoint(x: 1.0, y: 0.5)
}
backgroundColor = .clear
gradientLayer.frame = bounds
layer.insertSublayer(gradientLayer, at: 0)
}
}
USAGE
someView.applyGradient(isVertical: true, colorArray: [.green, .blue])
Since I only needed one type of gradient throughout my app I created a subclass of UIView and preconfigured the gradient layer on initialization with fixed colors.
The initializers of UIView call the configureGradientLayer-method, which configures the CAGradientLayer:
DDGradientView.h:
#import <UIKit/UIKit.h>
#interface DDGradientView : UIView {
}
#end
DDGradientView.m:
#import "DDGradientView.h"
#implementation DDGradientView
// Change the views layer class to CAGradientLayer class
+ (Class)layerClass
{
return [CAGradientLayer class];
}
- (instancetype)initWithCoder:(NSCoder *)aDecoder {
self = [super initWithCoder:aDecoder];
if(self) {
[self configureGradientLayer];
}
return self;
}
- (instancetype)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if(self) {
[self configureGradientLayer];
}
return self;
}
// Make custom configuration of your gradient here
- (void)configureGradientLayer {
CAGradientLayer *gLayer = (CAGradientLayer *)self.layer;
gLayer.colors = [NSArray arrayWithObjects:(id)[[UIColor whiteColor] CGColor], (id)[[UIColor lightGrayColor] CGColor], nil];
}
#end
I've extended the accepted answer a little using Swift's extension functionality as well as an enum.
Oh and if you are using Storyboard like I do, make sure to call gradientBackground(from:to:direction:) in viewDidLayoutSubviews() or later.
Swift 3
enum GradientDirection {
case leftToRight
case rightToLeft
case topToBottom
case bottomToTop
}
extension UIView {
func gradientBackground(from color1: UIColor, to color2: UIColor, direction: GradientDirection) {
let gradient = CAGradientLayer()
gradient.frame = self.bounds
gradient.colors = [color1.cgColor, color2.cgColor]
switch direction {
case .leftToRight:
gradient.startPoint = CGPoint(x: 0.0, y: 0.5)
gradient.endPoint = CGPoint(x: 1.0, y: 0.5)
case .rightToLeft:
gradient.startPoint = CGPoint(x: 1.0, y: 0.5)
gradient.endPoint = CGPoint(x: 0.0, y: 0.5)
case .bottomToTop:
gradient.startPoint = CGPoint(x: 0.5, y: 1.0)
gradient.endPoint = CGPoint(x: 0.5, y: 0.0)
default:
break
}
self.layer.insertSublayer(gradient, at: 0)
}
}
Swift Implementation:
var gradientLayerView: UIView = UIView(frame: CGRectMake(0, 0, view.bounds.width, 50))
var gradient: CAGradientLayer = CAGradientLayer()
gradient.frame = gradientLayerView.bounds
gradient.colors = [UIColor.grayColor().CGColor, UIColor.clearColor().CGColor]
gradientLayerView.layer.insertSublayer(gradient, atIndex: 0)
self.view.layer.insertSublayer(gradientLayerView.layer, atIndex: 0)
I have implemented this in swift with an extension:
Swift 3
extension UIView {
func addGradientWithColor(color: UIColor) {
let gradient = CAGradientLayer()
gradient.frame = self.bounds
gradient.colors = [UIColor.clear.cgColor, color.cgColor]
self.layer.insertSublayer(gradient, at: 0)
}
}
Swift 2.2
extension UIView {
func addGradientWithColor(color: UIColor) {
let gradient = CAGradientLayer()
gradient.frame = self.bounds
gradient.colors = [UIColor.clearColor().CGColor, color.CGColor]
self.layer.insertSublayer(gradient, atIndex: 0)
}
}
No I can set a gradient on every view like this:
myImageView.addGradientWithColor(UIColor.blue)
A Swift Approach
This answer builds on the answers above and provides implementation for dealing with the problem of the gradient not being properly applied during rotation. It satisfies this problem by changing the gradient layer to a square so that rotation in all directions results in a correct gradient. The function signature includes a Swift variadic argument that allows one to pass in as many CGColorRef's (CGColor) as needed (see sample usage). Also provided is an example as a Swift extension so that one can apply a gradient to any UIView.
func configureGradientBackground(colors:CGColorRef...){
let gradient: CAGradientLayer = CAGradientLayer()
let maxWidth = max(self.view.bounds.size.height,self.view.bounds.size.width)
let squareFrame = CGRect(origin: self.view.bounds.origin, size: CGSizeMake(maxWidth, maxWidth))
gradient.frame = squareFrame
gradient.colors = colors
view.layer.insertSublayer(gradient, atIndex: 0)
}
To use:
in viewDidLoad...
override func viewDidLoad() {
super.viewDidLoad()
configureGradientBackground(UIColor.redColor().CGColor, UIColor.whiteColor().CGColor)
}
Extension implementation
extension CALayer {
func configureGradientBackground(colors:CGColorRef...){
let gradient = CAGradientLayer()
let maxWidth = max(self.bounds.size.height,self.bounds.size.width)
let squareFrame = CGRect(origin: self.bounds.origin, size: CGSizeMake(maxWidth, maxWidth))
gradient.frame = squareFrame
gradient.colors = colors
self.insertSublayer(gradient, atIndex: 0)
}
}
Extension use-case example:
override func viewDidLoad() {
super.viewDidLoad()
self.view.layer.configureGradientBackground(UIColor.purpleColor().CGColor, UIColor.blueColor().CGColor, UIColor.whiteColor().CGColor)
}
Which means the gradient background can now be applied to any UIControl since all controls are UIViews (or a subclass) and all UIViews have CALayers.
Swift 4
Extension implementation
extension CALayer {
public func configureGradientBackground(_ colors:CGColor...){
let gradient = CAGradientLayer()
let maxWidth = max(self.bounds.size.height,self.bounds.size.width)
let squareFrame = CGRect(origin: self.bounds.origin, size: CGSize(width: maxWidth, height: maxWidth))
gradient.frame = squareFrame
gradient.colors = colors
self.insertSublayer(gradient, at: 0)
}
}
Extension use-case example:
override func viewDidLoad() {
super.viewDidLoad()
self.view.layer.configureGradientBackground(UIColor.purple.cgColor, UIColor.blue.cgColor, UIColor.white.cgColor)
}
What you are looking for is CAGradientLayer. Every UIView has a layer - into that layer you can add sublayers, just as you can add subviews. One specific type is the CAGradientLayer, where you give it an array of colors to gradiate between.
One example is this simple wrapper for a gradient view:
http://oleb.net/blog/2010/04/obgradientview-a-simple-uiview-wrapper-for-cagradientlayer/
Note that you need to include the QuartZCore framework in order to access all of the layer parts of a UIView.
Swift 4:
Shows gradient in IB correctly:
#IBDesignable public class GradientView: UIView {
override open class var layerClass: AnyClass {
return CAGradientLayer.classForCoder()
}
required public init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
configureGradientLayer()
}
public override init(frame: CGRect) {
super.init(frame: frame)
configureGradientLayer()
}
func configureGradientLayer() {
let gradientLayer = layer as! CAGradientLayer
gradientLayer.colors = [UIColor(hex: 0x003399).cgColor, UIColor(hex: 0x00297b).cgColor]
}
}
Simple swift view based on Yuchen's version
class GradientView: UIView {
override class func layerClass() -> AnyClass { return CAGradientLayer.self }
lazy var gradientLayer: CAGradientLayer = {
return self.layer as! CAGradientLayer
}()
override init(frame: CGRect) {
super.init(frame: frame)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
}
Then you can use gradientLayer after initialization like this...
someView.gradientLayer.colors = [UIColor.whiteColor().CGColor, UIColor.blackColor().CGColor]
Its a good idea to call the solutions above to update layer on the
viewDidLayoutSubviews 
to get the views updated correctly
My solution is to create UIView subclass with CAGradientLayer accessible as a readonly property. This will allow you to customize your gradient how you want and you don't need to handle layout changes yourself. Subclass implementation:
#interface GradientView : UIView
#property (nonatomic, readonly) CAGradientLayer *gradientLayer;
#end
#implementation GradientView
+ (Class)layerClass
{
return [CAGradientLayer class];
}
- (CAGradientLayer *)gradientLayer
{
return (CAGradientLayer *)self.layer;
}
#end
Usage:
self.iconBackground = [GradientView new];
[self.background addSubview:self.iconBackground];
self.iconBackground.gradientLayer.colors = #[(id)[UIColor blackColor].CGColor, (id)[UIColor whiteColor].CGColor];
self.iconBackground.gradientLayer.startPoint = CGPointMake(1.0f, 1.0f);
self.iconBackground.gradientLayer.endPoint = CGPointMake(0.0f, 0.0f);
SWIFT 3
To add a gradient layer on your view
Bind your view outlet
#IBOutlet var YOURVIEW : UIView!
Define the CAGradientLayer()
var gradient = CAGradientLayer()
Here is the code you have to write in your viewDidLoad
YOURVIEW.layoutIfNeeded()
gradient.startPoint = CGPoint(x: CGFloat(0), y: CGFloat(1))
gradient.endPoint = CGPoint(x: CGFloat(1), y: CGFloat(0))
gradient.frame = YOURVIEW.bounds
gradient.colors = [UIColor.red.cgColor, UIColor.green.cgColor]
gradient.colors = [ UIColor(red: 255.0/255.0, green: 56.0/255.0, blue: 224.0/255.0, alpha: 1.0).cgColor,UIColor(red: 86.0/255.0, green: 13.0/255.0, blue: 232.0/255.0, alpha: 1.0).cgColor,UIColor(red: 16.0/255.0, green: 173.0/255.0, blue: 245.0/255.0, alpha: 1.0).cgColor]
gradient.locations = [0.0 ,0.6 ,1.0]
YOURVIEW.layer.insertSublayer(gradient, at: 0)
In Swift 3.1
I have added this extension to UIView
import Foundation
import UIKit
import CoreGraphics
extension UIView {
func gradientOfView(withColours: UIColor...) {
var cgColours = [CGColor]()
for colour in withColours {
cgColours.append(colour.cgColor)
}
let grad = CAGradientLayer()
grad.frame = self.bounds
grad.colors = cgColours
self.layer.insertSublayer(grad, at: 0)
}
}
which I then call with
class OverviewVC: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
self.view.gradientOfView(withColours: UIColor.red,UIColor.green, UIColor.blue)
}
}
I have implemented this in my code.
UIView *view1 = [[UIView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, self.view.frame.size.width, 31.0f)];
view1.backgroundColor = [UIColor clearColor];
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = view1.bounds;
UIColor *topColor = [UIColor colorWithRed:132.0/255.0 green:222.0/255.0 blue:109.0/255.0 alpha:1.0];
UIColor *bottomColor = [UIColor colorWithRed:31.0/255.0 green:150.0/255.0 blue:99.0/255.0 alpha:1.0];
gradient.colors = [NSArray arrayWithObjects:(id)[topColor CGColor], (id)[bottomColor CGColor], nil];
[view1.layer insertSublayer:gradient atIndex:0];
Now I can see a gradient on my view.
To give gradient color to UIView (swift 4.2)
func makeGradientLayer(`for` object : UIView, startPoint : CGPoint, endPoint : CGPoint, gradientColors : [Any]) -> CAGradientLayer {
let gradient: CAGradientLayer = CAGradientLayer()
gradient.colors = gradientColors
gradient.locations = [0.0 , 1.0]
gradient.startPoint = startPoint
gradient.endPoint = endPoint
gradient.frame = CGRect(x: 0, y: 0, w: object.frame.size.width, h: object.frame.size.height)
return gradient
}
How to use
let start : CGPoint = CGPoint(x: 0.0, y: 1.0)
let end : CGPoint = CGPoint(x: 1.0, y: 1.0)
let gradient: CAGradientLayer = makeGradientLayer(for: cell, startPoint: start, endPoint: end, gradientColors: [
UIColor(red:0.92, green:0.07, blue:0.4, alpha:1).cgColor,
UIColor(red:0.93, green:0.11, blue:0.14, alpha:1).cgColor
])
self.vwTemp.layer.insertSublayer(gradient, at: 0)
This framework is good for gradients and other UI modifications in Historyboard: Design and prototype customized UI, interaction, navigation, transition and animation for App Store ready Apps in Interface Builder with IBAnimatable.
With this you can select a view, set the class to AnimatableView, and from Interface Builder property set gradients and preview results in realtime.
See this to know how apply gradients to UIView.

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