androidstringandroid-studiokotlin

How to remove first char in kotlin string

I'm trying to make a calculator in Android Studio with Kotlin and I trying to allow users to make numbers negative and positive, but I got only half of it, making number negative, but can't make it so it turns back to positive, for it I need to remove first char in string, someone knows how to do it?

var firstNumber: String = ...
if (firstNumber[0] == '-') {
   firstNumber.
}
Solution

  • You could use substring:

    firstNumber = firstNumber.substring(1);