Button border color - Objective C - Swift

Question

I want to change my border color to a specific hex color(#21CE99), can you guys please help me?

I\'ve already known how to change it to a basic color, for example:

Answer 1

The correct answer for people using SWIFT 4 would be:

_button.layer.borderColor = UIColor(red: 33/255, green: 206/255, blue: 153/255, alpha: 1.0).cgColor

Built-In UIColors Presets or your own colors:

_button.layer.borderColor = UIColor.blue.cgColor