Cannot set UIScrollView contentSize based on UIIMage - ios

Question

I am struggling for 2 hours now to get a UIScrollView.contentSize with the size of a UIImage, but the UIImage doesn't return a proper size, I have no idea why.
The result is that my scrollView content is square(the same as the scrollView's frame) and I can't scroll to the side of the image.
This is really frustrating! You can see in the debugger that my image1.size is invalid.

Answer 1

you are accessing an image from array which doesn't exist see your console log it's clearly saying index out of range. that's why your not getting any size and height as well because there's no image in the specific index

Answer 2

Your image view size is showing wrong because your scrollview content size is wrong. Use this method than print your image view frame. It will work
override func viewDidLayoutSubviews()
{
self.scrollView1.delegate = self
self.scrollView1.contentSize = CGSize(width:self.view.frame.size.width, height: self.view.frame.size.height)
}

Answer 3

OK, I have been struggling with this for a while now, and finally I was able to find the answer. The problem was indeed in the content size, and I was finally able to calculate it correctly as below:
let tempScrollView = UIScrollView(frame: self.imageLocationsArray[imageID])
let tempImageView = UIImageView(image: image)
//determine proportions of image against frame
let imageWidthFactor = image.size.width / tempScrollView.frame.width
let imageHeightFactor = image.size.height / tempScrollView.frame.height
//image is too wide
if imageWidthFactor > imageHeightFactor {
tempImageView.frame = CGRect(x: 0, y: 0, width: tempScrollView.frame.width * imageWidthFactor / imageHeightFactor, height: tempScrollView.frame.height)
}
//image is too tall
else {
tempImageView.frame = CGRect(x: 0, y: 0, width: tempScrollView.frame.width, height: tempScrollView.frame.height * imageHeightFactor / imageWidthFactor)
}