Programmatically create a UIView with color gradient

ios uiview uicolor
Allan Jiang picture Allan Jiang · Apr 15, 2014 · Viewed 236.2k times · Source

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?

Answer

Arslan Ali picture Arslan Ali · Apr 15, 2014

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.

Related questions

How to add constraints programmatically using Swift

I'm trying to figure this out since last week without going any step further. Ok, so I need to apply some constraints programmatically in Swift to a UIView using this code: var new_view:UIView! = UIView(frame: CGRectMake(0, 0, 100, 100)); new_view.…

Read More
How to add a touch event to a UIView?

How do I add a touch event to a UIView? I try: UIView *headerView = [[[UIView alloc] initWithFrame:CGRectMake(0, 0, tableView.bounds.size.width, nextY)] autorelease]; [headerView addTarget:self action:@selector(myEvent:) forControlEvents:UIControlEventTouchDown]; // ERROR MESSAGE: UIView may not respond to '-addTarget:…

Read More
Giving UIView rounded corners

My login view has a subview which has a UIActivityView and a UILabel saying "Signing In…". This subview has corners which aren't rounded. How can I make them round? Is there any way to do it inside my xib?

Read More