UISlider making it square not rounded - swift

Question

why does it do this? how can i change it? and is there anyway to change the slider so the progress slider is not rounded but square?
http://imgur.com/F9Ye24v
I would prefer it to be square, the code is just a normal UI slider implementation. I only edited the
override func trackRectForBounds(bounds: CGRect) -> CGRect {
return CGRectMake(0, 0, self.frame.width, 25)
}
to make the bar taller

Answer 1

You can set the minimum and maximum track image.
Just use an image (rectangle without corner radius) with a width of 1px and height of 25px.
https://developer.apple.com/library/ios/documentation/UIKit/Reference/UISlider_Class/#//apple_ref/doc/uid/TP40006798-CH3-SW21
Sample:
slider.setMinimumTrackImage(UIImage(named: "back"), forState: UIControlState.Normal)
slider.setMaximumTrackImage(UIImage(named: "back"), forState: UIControlState.Normal)
The back image is just a blue square image of size 25px.
The back Image: (just copy and paste)

Answer 2

slider.setMaximumTrackImage(UIImage.imageWith(color: .yellow), for: .normal)
slider.setMinimumTrackImage(UIImage.imageWith(color: .cyan), for: .normal)
UIImage extension:
static func imageWith(color: UIColor, size: CGSize? = nil) -> UIImage? {
let rect = CGRect(x: 0, y: 0, width: size?.width ?? 1, height: size?.height ?? 1)
UIGraphicsBeginImageContext(rect.size)
let context = UIGraphicsGetCurrentContext()
context?.setFillColor(color.cgColor)
context?.fill(rect)
let image = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return image
}

Answer 3

Simple
slider.setMinimumTrackImage(getImageWithColor(color: .blue, size: slider.frame.size), for: .normal)
func getImageWithColor(color: UIColor, size: CGSize) -> UIImage {
let rect = CGRect(x: 0, y: 0, width: size.width, height: size.height)
UIGraphicsBeginImageContextWithOptions(size, false, 0)
color.setFill()
UIRectFill(rect)
let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
return image
}