I have one UILabel, and i want to fade the end of the string, that is going to be out of bounds. What is the better solution for this?
Should i calculate the width of the label, compare it with the string width, and if string width is bigger than label's, i should fade last two letters? How exactly should i do that?
I hope it will be easy. Please write your solutions. Thanks!
I prefer to use this method for calculating the width:
CGRect labelRect = [text
boundingRectWithSize:labelSize
options:NSStringDrawingUsesLineFragmentOrigin
attributes:#{
NSFontAttributeName : [UIFont systemFontOfSize:14]
}
context:nil];
Swift 4.0 example:
let gradient = CAGradientLayer()
gradient.frame = titleLabel.bounds
gradient.colors = [UIColor.white.cgColor, UIColor.clear.cgColor]
gradient.startPoint = CGPoint(x: 0.1, y: 0.0)
gradient.endPoint = CGPoint(x: 0.95, y: 0.0)
label.lineBreakMode = .byClipping
label.layer.mask = gradient
result:
You can fade one line label using CAGradientLayer
CAGradientLayer *l = [CAGradientLayer layer];
l.frame = self.textLabel.bounds;
l.colors = #[(id)[UIColor whiteColor].CGColor, (id)[UIColor clearColor].CGColor];
l.startPoint = CGPointMake(0.1f, 1.0f);
l.endPoint = CGPointMake(0.95f, 1.0f);
self.textLabel.layer.mask = l;
Works only from layoutSubviews() method
override func layoutSubviews() {
super.layoutSubviews()
let maskLayer = CALayer()
maskLayer.frame = label.bounds
let gradientLayer = CAGradientLayer()
gradientLayer.frame = label.bounds
gradientLayer.colors = [UIColor.white.cgColor, UIColor.clear.cgColor]
gradientLayer.startPoint = CGPoint(x: 0.7, y: 0.0)
gradientLayer.endPoint = CGPoint(x: 0.95, y: 0.0)
maskLayer.addSublayer(gradientLayer)
label.layer.mask = maskLayer
}
2023. Typical OUTLINE solution:
It does not take in to account language direction, it assumes background is white, etc etc.
Note that you have to explicitly decide on and set the length of the fade, which, of course, will be constant through out the app, you can't use ".1 of the width of the text". Here we use the height of the label which works well.
class FadeyLabel: UIILabel {
lazy var fade: CAGradientLayer = {
let g = CAGradientLayer()
g.colors = [UIColor.white.withAlphaComponent(0).cgColor,
UIColor.white.withAlphaComponent(1).cgColor]
g.startPoint = CGPoint(x: 0, y: 0)
g.endPoint = CGPoint(x: 1, y: 0)
layer.addSublayer(g)
return g
}()
override func layoutSubviews() {
super.layoutSubviews()
fade.frame = CGRect(
origin: CGPoint(x: bounds.width - bounds.height, y: 0),
size: CGSize(width: bounds.height, height: bounds.height))
}
}
I've found the answer - i should use GTMFadeTruncatingLabelTest class from google
Related
I have to follow through my designer's gradient layer as shown below and I'm running into a wall trying to replicate her design (below).
I have the following code to try to replicate the same shadow but it is too solid compared to her gradient. How do I reduce my layer to have a gradient look and feel?
backgroundView.layer.shadowColor = UIColor.Custom.darkBlue.cgColor
backgroundView.layer.shadowOpacity = 1.0
backgroundView.layer.shadowRadius = 10
EDIT:
I implemented what I needed using #Frankenstein's solution below.
backgroundView.backgroundColor = UIColor.Custom.darkBlue
let gradient: CAGradientLayer = CAGradientLayer()
gradient.colors = [UIColor.black.cgColor, UIColor.Custom.darkBlue.cgColor]
gradient.frame = CGRect(x: backgroundView.frame.origin.x, y: backgroundView.frame.origin.y - 39, width: view.bounds.width, height: 40)
view.layer.addSublayer(gradient)
With the expected result below. Thank you!
You need to add a new CAGradientLayer and not set the shadow, here is an example:
let gradient: CAGradientLayer = CAGradientLayer()
gradient.colors = [UIColor.black.cgColor, UIColor.Custom.darkBlue.cgColor]
gradient.locations = [0.0 , 1.0]
gradient.startPoint = CGPoint(x: 0.0, y: 1.0)
gradient.endPoint = CGPoint(x: 1.0, y: 1.0)
gradient.frame = view.bounds
view.layer.addSublayer(gradient)
Here is how you can achieve that
let gradient: CAGradientLayer = CAGradientLayer()
gradient.colors = [UIColor.black.cgColor, UIColor.blue.cgColor]
gradient.locations = [0.0 , 1.0]
gradient.startPoint = CGPoint(x : 0.0, y : 0)
gradient.endPoint = CGPoint(x :0.0, y: 0.15) // you need to play with 0.15 to adjust gradient vertically
gradient.frame = view.bounds
view.layer.addSublayer(gradient)
With 0.15 to 0.5 you get
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.
I want to set border color with the gradient left to right [Red, Green] at UIView.
Like example:
I tried below code: -
class View: UIView {
override func layoutSubviews() {
super.layoutSubviews()
let path = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: [.topLeft, .bottomLeft, .topRight, .bottomRight], cornerRadii: CGSize(width: frame.size.height / 2, height: frame.size.height / 2))
let gradient = CAGradientLayer()
gradient.frame = CGRect(origin: CGPoint.zero, size: frame.size)
gradient.colors = [UIColor.green.cgColor, UIColor.red.cgColor]
let shape = CAShapeLayer()
shape.lineWidth = 10
shape.path = path.cgPath
shape.strokeColor = UIColor.black.cgColor
shape.fillColor = UIColor.clear.cgColor
gradient.mask = shape
layer.insertSublayer(gradient, at: 0)
}
}
There is three problem which I am not able to resolve: -
1- I have set lineWidth 10 but its showing width 10 at corners and at horizontal/vertical only 5.
2- I want to show the gradient from left to right not top to bottom.
I tried below code to set gradient from left to right but not working: -
// gradient.frame = CGRect(origin: CGPoint.zero, size: frame.size)
gradient.startPoint = CGPoint(x: 0.0, y: 0.5)
gradient.endPoint = CGPoint(x: 1.0, y: 0.5)
Please help. Thanks in advance.
Edit
I want to set border from left to right
You need to change gradient.startPoint and gradient.endPoint
enum Direction {
case horizontal
case vertical
}
class View: UIView {
init(frame: CGRect, cornerRadius: CGFloat, colors: [UIColor], lineWidth: CGFloat = 5, direction: Direction = .horizontal) {
super.init(frame: frame)
self.layer.cornerRadius = cornerRadius
self.layer.masksToBounds = true
let gradient = CAGradientLayer()
gradient.frame = CGRect(origin: CGPoint.zero, size: self.frame.size)
gradient.colors = colors.map({ (color) -> CGColor in
color.cgColor
})
switch direction {
case .horizontal:
gradient.startPoint = CGPoint(x: 0, y: 1)
gradient.endPoint = CGPoint(x: 1, y: 1)
case .vertical:
gradient.startPoint = CGPoint(x: 0, y: 0)
gradient.endPoint = CGPoint(x: 0, y: 1)
}
let shape = CAShapeLayer()
shape.lineWidth = lineWidth
shape.path = UIBezierPath(roundedRect: self.bounds.insetBy(dx: lineWidth,
dy: lineWidth), cornerRadius: cornerRadius).cgPath
shape.strokeColor = UIColor.black.cgColor
shape.fillColor = UIColor.clear.cgColor
gradient.mask = shape
self.layer.addSublayer(gradient)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
As you can see, I added some extra parameters. I solved this issue by adding inset to the roundedRect:
shape.path = UIBezierPath(roundedRect: self.bounds.insetBy(dx: lineWidth,
dy: lineWidth), cornerRadius: cornerRadius).cgPath
How to use it:
let myView = View(frame: CGRect(x: 0, y: 0, width: 200, height: 50), cornerRadius: 25, colors: [UIColor.red, .orange, .yellow], lineWidth: 2, direction: .horizontal)
myView.center = view.center
view.addSubview(myView)
Screenshot:
roundedViewWithGradient
The problem is that the the bezier path is not drawn inside its bounds. It's drawn around its bounds. So half the stroke width is inside and half is outside. You need to adjust the bounds to deal with this.
Change the frame you pass into the bezier path from self.bounds to self.bounds.insetBy(dx: 5, dy: 5) where 5 is half your line width.
And the lines:
gradient.startPoint = CGPoint(x: 0.0, y: 0.5)
gradient.endPoint = CGPoint(x: 1.0, y: 0.5)
do result in the gradient going from left to right.
Here is fully working code from yours:
class View: UIView {
override func layoutSubviews() {
super.layoutSubviews()
let path = UIBezierPath(roundedRect: self.bounds.insetBy(dx: 5, dy: 5), byRoundingCorners: [.topLeft, .bottomLeft, .topRight, .bottomRight], cornerRadii: CGSize(width: frame.size.height / 2, height: frame.size.height / 2))
let gradient = CAGradientLayer()
gradient.frame = CGRect(origin: CGPoint.zero, size: frame.size)
gradient.startPoint = CGPoint(x: 0.0, y: 0.5)
gradient.endPoint = CGPoint(x: 1.0, y: 0.5)
gradient.colors = [UIColor.green.cgColor, UIColor.red.cgColor]
let shape = CAShapeLayer()
shape.lineWidth = 10
shape.path = path.cgPath
shape.strokeColor = UIColor.black.cgColor
shape.fillColor = UIColor.clear.cgColor
gradient.mask = shape
layer.insertSublayer(gradient, at: 0)
}
}
I want to make a UIView have an effect of transparent gradient from the middle to the left and right. Like in this example:
The word 籍 has the desired effect. This view is achieved by the class MarqueeLabel. I examined the source code, it is likely implemented by class CALayer.
In Swift 4: for top to bottom transparent gradient.
let gradient = CAGradientLayer()
gradient.startPoint = CGPoint(x: 0.5, y: 0.0)
gradient.endPoint = CGPoint(x: 0.5, y: 0.6)
let whiteColor = UIColor.white
gradient.colors = [whiteColor.withAlphaComponent(0.0).cgColor, whiteColor.withAlphaComponent(1.0).cgColor, whiteColor.withAlphaComponent(1.0).cgColor]
gradient.locations = [NSNumber(value: 0.0),NSNumber(value: 0.2),NSNumber(value: 1.0)]
gradient.frame = gradientView.bounds
gradientView.layer.mask = gradient
Screenshot
Swift code
let mask = CAGradientLayer()
mask.startPoint = CGPointMake(0.0, 0.5)
mask.endPoint = CGPointMake(1.0, 0.5)
let whiteColor = UIColor.whiteColor()
mask.colors = [whiteColor.colorWithAlphaComponent(0.0).CGColor,whiteColor.colorWithAlphaComponent(1.0),whiteColor.colorWithAlphaComponent(1.0).CGColor]
mask.locations = [NSNumber(double: 0.0),NSNumber(double: 0.2),NSNumber(double: 1.0)]
mask.frame = label.bounds
label.layer.mask = mask
You can use CAGradientLayer as following.
gradientLayer = [CAGradientLayer layer];
gradientLayer.frame = baseView.bounds;
gradientLayer.startPoint = CGPointMake(0.5,0.0);
gradientLayer.endPoint = CGPointMake(0.5,1.0);
gradientLayer.locations = #[#(0.0), #(0.2), #(1.0)];
gradientLayer.colors = #[(id)[UIColor colorWithWhite:1.0 alpha:0.9].CGColor,
(id)[UIColor colorWithWhite:1.0 alpha:0.3].CGColor,
(id)[UIColor colorWithWhite:1.0 alpha:0.0].CGColor];
[baseView.layer addSublayer:gradientLayer];
CAGradientLayer supports several properties to make natural gradient, such as setting gradient direction by startPoint and endPoint, changing color curve by locations and colors.
You also make a transparent effect by using alpha channel of color.
Swift 3:
let mask = CAGradientLayer()
mask.startPoint = CGPoint(x: 0, y: 0.5)
mask.endPoint = CGPoint(x:1.0, y:0.5)
let whiteColor = UIColor.white
mask.colors = [whiteColor.withAlphaComponent(0.0).cgColor,whiteColor.withAlphaComponent(1.0),whiteColor.withAlphaComponent(1.0).cgColor]
mask.locations = [NSNumber(value: 0.0),NSNumber(value: 0.2),NSNumber(value: 1.0)]
mask.frame = view.bounds
view.layer.mask = mask
Use clear color instead of set the alpha value.
let gradientLayer = CAGradientLayer()
gradientLayer.startPoint = CGPoint(x: 0, y: 0.5)
gradientLayer.endPoint = CGPoint(x: 1, y: 0.5)
gradientLayer.colors = [UIColor.clear.cgColor, UIColor.white.cgColor, UIColor.white.cgColor]
gradientLayer.locations = [0, 0.2, 1]
gradientLayer.frame = gradientView.bounds
gradientView.layer.mask = gradientLayer
I want to make a gradient border of view like the following picture:
but I don't know how do it exactly , i.e. what the gradient color I should use to do it? how to set my view to show a border like the image?
I'm using the following code to get a border:
self.view.layer.borderColor = [UIColor orangeColor].CGColor;
self.view.layer.borderWidth = 2.0f;
This what i did and it worked perfectly
extension CALayer {
func addGradienBorder(colors:[UIColor],width:CGFloat = 1) {
let gradientLayer = CAGradientLayer()
gradientLayer.frame = CGRect(origin: CGPointZero, size: self.bounds.size)
gradientLayer.startPoint = CGPointMake(0.0, 0.5)
gradientLayer.endPoint = CGPointMake(1.0, 0.5)
gradientLayer.colors = colors.map({$0.CGColor})
let shapeLayer = CAShapeLayer()
shapeLayer.lineWidth = width
shapeLayer.path = UIBezierPath(rect: self.bounds).CGPath
shapeLayer.fillColor = nil
shapeLayer.strokeColor = UIColor.blackColor().CGColor
gradientLayer.mask = shapeLayer
self.addSublayer(gradientLayer)
}
}
Thanx Tiago Mendes for answer.
I improved functionality:
added corner radius.
And fixed some issues to ensure correct masking and given border width:
improved gradient layer frame;
improved mask path rounding rect.
Swift 5
public extension UIView {
private static let kLayerNameGradientBorder = "GradientBorderLayer"
func gradientBorder(width: CGFloat,
colors: [UIColor],
startPoint: CGPoint = CGPoint(x: 0.5, y: 0.0),
endPoint: CGPoint = CGPoint(x: 0.5, y: 1.0),
andRoundCornersWithRadius cornerRadius: CGFloat = 0) {
let existingBorder = gradientBorderLayer()
let border = existingBorder ?? CAGradientLayer()
border.frame = CGRect(x: bounds.origin.x, y: bounds.origin.y,
width: bounds.size.width + width, height: bounds.size.height + width)
border.colors = colors.map { return $0.cgColor }
border.startPoint = startPoint
border.endPoint = endPoint
let mask = CAShapeLayer()
let maskRect = CGRect(x: bounds.origin.x + width/2, y: bounds.origin.y + width/2,
width: bounds.size.width - width, height: bounds.size.height - width)
mask.path = UIBezierPath(roundedRect: maskRect, cornerRadius: cornerRadius).cgPath
mask.fillColor = UIColor.clear.cgColor
mask.strokeColor = UIColor.white.cgColor
mask.lineWidth = width
border.mask = mask
let exists = (existingBorder != nil)
if !exists {
layer.addSublayer(border)
}
}
private func gradientBorderLayer() -> CAGradientLayer? {
let borderLayers = layer.sublayers?.filter { return $0.name == UIView.kLayerNameGradientBorder }
if borderLayers?.count ?? 0 > 1 {
fatalError()
}
return borderLayers?.first as? CAGradientLayer
}
}
And for more readable declaration of startPoint and endPoint of gradient layer I use this code:
public extension CGPoint {
enum CoordinateSide {
case topLeft, top, topRight, right, bottomRight, bottom, bottomLeft, left
}
static func unitCoordinate(_ side: CoordinateSide) -> CGPoint {
switch side {
case .topLeft: return CGPoint(x: 0.0, y: 0.0)
case .top: return CGPoint(x: 0.5, y: 0.0)
case .topRight: return CGPoint(x: 1.0, y: 0.0)
case .right: return CGPoint(x: 0.0, y: 0.5)
case .bottomRight: return CGPoint(x: 1.0, y: 1.0)
case .bottom: return CGPoint(x: 0.5, y: 1.0)
case .bottomLeft: return CGPoint(x: 0.0, y: 1.0)
case .left: return CGPoint(x: 1.0, y: 0.5)
}
}
}
So final usage is:
view.gradientBorder(width: 3, colors: [.red, .orange], startPoint: .unitCoordinate(.top), endPoint: .unitCoordinate(.bottom), andRoundCornersWithRadius: 12)
You can make gradient border of view and corner radius(if you want) using this--
self.yourView.layer.cornerRadius=4;
self.yourView.layer.masksToBounds=YES;
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = self.yourView.bounds;
gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor colorWithRed:255/255.0 green:226/255.0 blue:138/255.0 alpha:1.0] CGColor], (id)[[UIColor colorWithRed:255/255.0 green:198/255.0 blue:91/255.0 alpha:0.9] CGColor],(id)[[UIColor colorWithRed:255/255.0 green:226/255.0 blue:138/255.0 alpha:1.0] CGColor], nil];
gradient.startPoint = CGPointMake(0.0, 0.0);
gradient.endPoint = CGPointMake(1, 1);
CAShapeLayer *shapeLayer =[[CAShapeLayer alloc] init];
shapeLayer.lineWidth = 15; // higher number higher border width
shapeLayer.path = [UIBezierPath bezierPathWithRect:self.yourView.bounds].CGPath;
shapeLayer.fillColor = nil;
shapeLayer.strokeColor = [UIColor blackColor].CGColor;
gradient.mask = shapeLayer;
[self.yourView.layer insertSublayer:gradient atIndex:0];
this will help you! Thanks
Here is another solution that is working on swift 4
import UIKit
public extension UIView {
private static let kLayerNameGradientBorder = "GradientBorderLayer"
func setGradientBorder(
width: CGFloat,
colors: [UIColor],
startPoint: CGPoint = CGPoint(x: 0.5, y: 0),
endPoint: CGPoint = CGPoint(x: 0.5, y: 1)
) {
let existedBorder = gradientBorderLayer()
let border = existedBorder ?? CAGradientLayer()
border.frame = bounds
border.colors = colors.map { return $0.cgColor }
border.startPoint = startPoint
border.endPoint = endPoint
let mask = CAShapeLayer()
mask.path = UIBezierPath(roundedRect: bounds, cornerRadius: 0).cgPath
mask.fillColor = UIColor.clear.cgColor
mask.strokeColor = UIColor.white.cgColor
mask.lineWidth = width
border.mask = mask
let exists = existedBorder != nil
if !exists {
layer.addSublayer(border)
}
}
private func gradientBorderLayer() -> CAGradientLayer? {
let borderLayers = layer.sublayers?.filter { return $0.name == UIView.kLayerNameGradientBorder }
if borderLayers?.count ?? 0 > 1 {
fatalError()
}
return borderLayers?.first as? CAGradientLayer
}
}
How to use:
view.setGradientBorder(width: 10, colors: [UIColor(red: 47, green: 198, blue: 176), UIColor(red: 67, green: 210, blue: 128)])
Here is how you would do it with Core Graphics. Create a UIView subclass and in its drawRect: create a gradient and overlay that with a black content rectangle:
- (void)drawRect:(CGRect)rect
{
CGContextRef ctx = UIGraphicsGetCurrentContext();
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
// Create and draw the gradient
UIColor *gradientColorTop = [UIColor orangeColor];
UIColor *gradientColorBottom = [UIColor yellowColor];
NSArray *gradientColors = #[(id) gradientColorTop.CGColor, (id) gradientColorBottom.CGColor];
CGFloat locations[] = {0.1, 0.80};
CGGradientRef gradient = CGGradientCreateWithColors(colorSpace, (__bridge CFArrayRef)(gradientColors), locations);
CGPoint startPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMinY(rect));
CGPoint endPoint = CGPointMake(CGRectGetMidX(rect), CGRectGetMaxY(rect));
UIBezierPath *gradientBorder = [UIBezierPath bezierPathWithRoundedRect:rect
byRoundingCorners:UIRectCornerAllCorners cornerRadii:CGSizeMake(10.0, 10.0)];
[gradientBorder addClip];
CGContextDrawLinearGradient(ctx, gradient, startPoint, endPoint, 0);
// Draw the inner content rectangle
UIBezierPath *contentPath = [UIBezierPath bezierPathWithRect:CGRectInset(rect, 20.0, 20.0)];
[[UIColor blackColor] setFill];
[contentPath fill];
CGGradientRelease(gradient);
CGColorSpaceRelease(colorSpace);
}
That would produce a result similar to what you are trying to achieve.
objective-c version of Christos Hadjikyriacou's answer
#implementation CALayer(Border)
-(void) addGradientBorder {
CAGradientLayer *gradientLayer = [[CAGradientLayer alloc] init];
gradientLayer.frame = CGRectMake(0, 0, self.bounds.size.width, self.bounds.size.height);
gradientLayer.startPoint = CGPointMake(0.0, 0.5);
gradientLayer.endPoint = CGPointMake(1.0, 0.5);
gradientLayer.colors = #[(id)[UIColor redColor].CGColor, (id)[UIColor blueColor].CGColor];
CAShapeLayer *shapeLayer =[[CAShapeLayer alloc] init];
shapeLayer.lineWidth = 0.5;
shapeLayer.path = [UIBezierPath bezierPathWithRect:self.bounds].CGPath;
shapeLayer.fillColor = nil;
shapeLayer.strokeColor = [UIColor blackColor].CGColor;
gradientLayer.mask = shapeLayer;
[self addSublayer : gradientLayer];
}
#end