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Jonathan Fernandez
4,047 PointsIncorrect Autolayout equation?
At 6:42, the video displays an auto layout equation for the bottom of our view. However, it says: "view.Bottom = (1 * superview.Bottom) + 50.
Shouldn't it be "view.Bottom = (1 * superview.Bottom) - 50." Or even superview.Bottom = (1 * view.Bottom) + 50."
Again, I am not sure if this is right, I recently just read the linked Apple resources.
3 Answers
Maria Te
8,521 PointsYeah, thanks for the clarification man! Yeah, I tried both of your examples on Xcode and I found out that what you just said was true. Can I have that link to Apple?
Maria Te
8,521 PointsI watched that video too and when I typed
view.Bottom = (1 * superview.Bottom) + 50
it didn't work. I don't know which one of your options might be right, so if you find out can you tell me? I have a feeling that
superview.Bottom = (1 * view.Bottom) + 50
might work.
Jonathan Fernandez
4,047 PointsBoth are the same actually (just found out today through the Apple documentation). Intuitively, I would choose the first one I mentioned "view.Bottom = (1 * superview.Bottom) - 50." but Apple "recommends" that our constant be positive. So what we can do is "superview.Bottom = (1 * view.Bottom) + 50." The reason being is the = sign is an equality relationship, not an "Assignment operator" as we are use to in swift. Hoped that made sense!
Maria Te
8,521 PointsThanks!
Jonathan Fernandez
4,047 PointsJonathan Fernandez
4,047 PointsYeah, of course! https://developer.apple.com/library/content/documentation/UserExperience/Conceptual/AutolayoutPG/AnatomyofaConstraint.html#//apple_ref/doc/uid/TP40010853-CH9-SW1
The part that will help you understand our question is when Apple shows an example with a blue and red view. Below that it shows examples of autolayout equations.
This link should also be provided below the respective video by Treehouse.
Jonathan Fernandez
4,047 PointsJonathan Fernandez
4,047 PointsAlso, check out the section of "Equality, Not Assignment". Best of luck!