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iOS Build an Interactive Story App with Swift Creating the User Interface Programmatically Displaying the Story

Miguel Sousa
Miguel Sousa
6,872 Points

Where's the bottom constraint for storyLabel?

I don't understand why there's no necessity to add a bottom constraint for storyLabel. I thought all "sides" from views should be anchored to another view or to a parent view. In this video, we only have leading, top and trailing anchor for storyLabel.

Also, is there any difference between creating a Left/Right Anchor constraint to a Leading/Trailing Anchor constraint?

Hi Miguel,

Some views have intrinsic heights, UILabels are one of those views. Because a label 'knows' it's height, there is enough information to create an unambiguous layout. Usually an element requires 4 constraints; leading, trailing, top & bottom might be one way to constrain an element. An equally valid way might be leading, top, height & width. The important thing is that the layout in unambiguous - Autolayout evaluates all constraints to one and only one possible solution.

I think the leading, trailing accounts for multiple languages i.e. Arabic reads right to left, so in that case leading would be right and not left.

Hope that helps.

Happy coding!