Myujth

I have a UIImageView inside a ForecastCell Class (for a UICollectionView), anyhow, I can't get the UIImageView inside the cell to change it's size. This is what I tried:

private func setupWeatherIcon()
 self.addSubview(mWeatherIcon)

 //mWeatherIcon.frame.size.width = CGFloat(self.frame.width) / 2
 //mWeatherIcon.frame.size.height = CGFloat(self.frame.height) / 2
 mWeatherIcon.frame.size.width = 20
 mWeatherIcon.frame.size.height = 20

 mWeatherIcon.centerXAnchor.constraint(equalTo: self.safeAreaLayoutGuide.centerXAnchor).isActive = true
 mWeatherIcon.centerYAnchor.constraint(equalTo: self.safeAreaLayoutGuide.centerYAnchor).isActive = true

This is mWeatherIcon:

var mWeatherIcon: UIImageView = 
 let image = UIImageView(image: UIImage(named: "partly-cloudy"))

 image.translatesAutoresizingMaskIntoConstraints = false
 return image
()

No matter what width and height I set, It always stays the same width and height.

You need width and height constraints

self.contentView.addSubview(mWeatherIcon)

NSLayoutConstraint.activate([
 mWeatherIcon.centerXAnchor.constraint(equalTo:contentView.centerXAnchor),
 mWeatherIcon.centerYAnchor.constraint(equalTo:contentView.centerYAnchor),
 mWeatherIcon.widthAnchor.constraint(equalTo:contentView.widthAnchor,multiplier:0.5),
 mWeatherIcon.heightAnchor.constraint(equalTo:contentView.heightAnchor,multiplier:0.5)
])

Don't forget to implement this method

func collectionView(_ collectionView: UICollectionView, 
 layout collectionViewLayout: UICollectionViewLayout, 
 sizeForItemAt indexPath: IndexPath) -> CGSize