Shared Preference with type safety

SharedPrefs.kt

package com.example.application.util
// Created by Rafsanjani on 01/24/2020.

import android.content.Context

class SharedPrefs(context: Context) {
    companion object {
        //declare all constants here for things you would like to persist
        private const val IS_FIRST_TIME_LAUNCH = "com.example.application.is_first_time_launch"
    }
    
    //this will be the name of the xml file which will contain the key-value pairs of the preferences
    //we want to make this unique to our application. we can use context.packageName as well
    private val fileName = "com.example.application.shared_prefs"
    
    private val settings: SharedPreferences = context.getSharedPreferences(fileName, Context.MODE_PRIVATE)
    private val editor = settings.edit()
   
    /**
     * Store a value which tells the context that the application is starting for the first time. This is
     * for performing operations that are only necessary when the application is running for the first time
     *
     */
    var firstTimeLaunch: Boolean
        get() = settings.getBoolean(IS_FIRST_TIME_LAUNCH, true)
        set(isFirstTime) = editor.putBoolean(IS_FIRST_TIME_LAUNCH, isFirstTime).apply()
}