set the padding of a text field using swift in xcode

https://stackoverflow.com/a/27066764/846780

This answer is very clear,

1. If you subclass UITextField you can override textRectForBounds, editingRectForBounds and placeholderRectForBounds. These methods just allow you to add a rect (frame) to your textfield's label.

2. newBounds method create the rect (frame) that will be added to textfield's label.

3. Finally your padding is: let padding = UIEdgeInsets(top: 0, left: 5, bottom: 0, right: 5);

4. Now you have a custom UITextField that has a custom padding.

5. If you create your new subClass like this class MyTextField: UITextField for example, you only need to change the class of the UITextField that you've added into IB file.

Complementing the answer of klevison-matias this is the code I use when I want to add a padding to my TextField in Swift 3

//UITextField : override textRect, editingRect 
class LeftPaddedTextField: UITextField {

    override func textRect(forBounds bounds: CGRect) -> CGRect {
        return CGRect(x: bounds.origin.x + 10, y: bounds.origin.y, width: bounds.width, height: bounds.height)
    }

    override func editingRect(forBounds bounds: CGRect) -> CGRect {
        return CGRect(x: bounds.origin.x + 10, y: bounds.origin.y, width: bounds.width, height: bounds.height)
    }

}

Then in my TextField I use in this way:

let emailTextField: LeftPaddedTextField = {
    let textField = LeftPaddedTextField()
    textField.placeholder = "Enter email"
    textField.layer.borderColor = UIColor.lightGray.cgColor
    textField.layer.borderWidth = 1
    textField.keyboardType = .emailAddress
    return textField
}()

let passwordTextField: LeftPaddedTextField = {
    let textField = LeftPaddedTextField()
    textField.placeholder = "Enter password"
    textField.layer.borderColor = UIColor.lightGray.cgColor
    textField.layer.borderWidth = 1
    textField.isSecureTextEntry = true
    return textField
}()