Swift version: 5.6
If you wanted to pin a button to the left edge of its parent, you might write code like this:
button.leftAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leftAnchor).isActive = true
However, that has a problem: in right-to-left languages, the user interface ought to be flipped horizontally for the most part, but your button won’t move – you’ve specifically asked it to be pinned to the left edge regardless of the user’s device settings.
If that’s what you want, you don’t have a problem. However, if you meant “left edge for left-to-right languages and right edge for right-to-left languages,” then you should use leadingAnchor
instead of leftAnchor
, like this:
button.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor).isActive = true
For the same effect on the opposite edge, you should use trailingAnchor
rather than rightAnchor
. Again, if you specifically want something to appear on the right regardless of language then this does not apply.
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