Can I align a button's label with its layout margins? - ios

Question

One way to left-align a UIButton's title is to set the contentHorizontalAlignment to .left (or .leading). But this places the title flush with the left edge of the button with no margin. A common way to add some margin is to set the contentEdgeInstets.
But my button extends from once edge of the screen to the other, so I would like the left and right margins to honor the layoutMargins. These margins might change as the view is resized or the device is rotated.
Is there a way to set the button's insets to observe these margins? Or should I create a button from a custom view where I can use my own label and anchor it to the layoutMarginsGuide?

Answer 1

I guess you can manually set the margin of the button using titleEdgeInsets to match the inset of the Cancel Button.
Have a look at the following, the two buttons are exactly the same aside from the origin.y and the titleEdgeInsets:
let view = UIView(frame: CGRect(x: 0, y: 0, width: 400, height: 400))
view.backgroundColor = .white
let button = UIButton(frame: CGRect(x: 40, y: 40, width: 200, height: 80))
button.setTitle("Some really long title", for: .normal)
button.backgroundColor = .red
button.setTitleColor(.black, for: .normal)
let button2 = UIButton(frame: CGRect(x: 40, y: 160, width: 200, height: 80))
button2.setTitle("Some really long title", for: .normal)
button2.backgroundColor = .red
button2.setTitleColor(.black, for: .normal)
button2.titleEdgeInsets = UIEdgeInsets(top: 20, left: 20, bottom: 20, right: 20)
view.addSubview(button)
view.addSubview(button2)
It gives the following result:
Hope this helps :)

Answer 2

A subclassed button may work for you...
class RespectSuperviewMarginButton: UIButton {
override func layoutSubviews() {
super.layoutSubviews()
if let sv = superview {
contentEdgeInsets.left = sv.layoutMargins.left
}
}
}

Answer 3

My current best answer is: no, this is not possible without subclassing.
The subclass implementation I am currently using is simple enough:
class LayoutMarginRespectingButton: UIButton {
override func layoutSubviews() {
super.layoutSubviews()
contentEdgeInsets = layoutMargins
}
}