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iosiphoneswiftcoordinate-systemsscreen-size

Is there a way to convert coordinate points between different device sizes? (iOS)

I am following some tutorials online but the code is meant for an iPad. I am working with an iPhone and the screen sizes are different. The problem is that the author uses 'magic numbers' that are made specifically for the iPad.

I have been successful in creating conversions so that it will work for any device. For example:

let xMid : CGFloat = CGRectGetMidX(self.frame)
let yMid : CGFloat = CGRectGetMidY(self.frame)
print("x: \(xMid) y: \(yMid)")

let height : CGFloat = CGRectGetHeight(self.frame)
let width  : CGFloat = CGRectGetWidth (self.frame)

makeSlotAt(CGPoint(x: xMid / 4.0,              y: 0), isGood: true)
makeSlotAt(CGPoint(x: xMid - xMid / 4.0,       y: 0), isGood: false)
makeSlotAt(CGPoint(x: xMid + xMid / 4.0,       y: 0), isGood: true)
makeSlotAt(CGPoint(x: xMid * 2.0 - xMid / 4.0, y: 0), isGood: false)

makeBouncerAt(CGPoint(x: 0,          y: 0))
makeBouncerAt(CGPoint(x: xMid / 2.0, y: 0))
makeBouncerAt(CGPoint(x: xMid,       y: 0))
makeBouncerAt(CGPoint(x: xMid * 1.5, y: 0))
makeBouncerAt(CGPoint(x: xMid * 2.0, y: 0))

Anyway, I was just wondering if there was a function or cheat sheet that had numerical conversions between device sizes.

Thanks!

Solution

  • If the tutorial you're using uses magic numbers, then stop using it immediately. If you use autolayout and follow Apple's guidelines for iOS 7 & up, you rarely, if ever, need to use magic numbers. The functions that you created are a good start for in-code measurements.