Replacing image in clear button

To change default clear button icon, you have to create binding to your text field and then pass the following lines of code:

if let clearButton = someTextField.value(forKeyPath: "_clearButton") as? UIButton {
            clearButton.setImage(UIImage(named:"image_name"), for: .normal)
        }

To change size of the icon you can upload to the project the image with the appropriate size.