My class for request runtime permissions in Activity or Fragment
It also help you show rationale or open Setting to enable permission after user denied a permission (with/without Never ask again) option easier 
class RequestPermissionHandler(private val activity: Activity? = null,
                               private val fragment: Fragment? = null,
                               private val permissions: Set<String> = hashSetOf(),
                               private val listener: Listener? = null
) {
    private var hadShowRationale: Boolean = false
    fun requestPermission() {
        hadShowRationale = showRationaleIfNeed()
        if (!hadShowRationale) {
            doRequestPermission(permissions)
        }
    }
    fun retryRequestDeniedPermission() {
        doRequestPermission(permissions)
    }
    private fun showRationaleIfNeed(): Boolean {
        val unGrantedPermissions = getPermission(permissions, Status.UN_GRANTED)
        val permanentDeniedPermissions = getPermission(unGrantedPermissions, Status.PERMANENT_DENIED)
        if (permanentDeniedPermissions.isNotEmpty()) {
            val consume = listener?.onShowSettingRationale(unGrantedPermissions)
            if (consume != null && consume) {
                return true
            }
        }
        val temporaryDeniedPermissions = getPermission(unGrantedPermissions, Status.TEMPORARY_DENIED)
        if (temporaryDeniedPermissions.isNotEmpty()) {
            val consume = listener?.onShowPermissionRationale(temporaryDeniedPermissions)
            if (consume != null && consume) {
                return true
            }
        }
        return false
    }
    fun requestPermissionInSetting() {
        val intent = Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS)
        val packageName = activity?.packageName ?: run {
            fragment?.requireActivity()?.packageName
        }
        val uri = Uri.fromParts("package", packageName, null)
        intent.data = uri
        activity?.apply {
            startActivityForResult(intent, REQUEST_CODE)
        } ?: run {
            fragment?.startActivityForResult(intent, REQUEST_CODE)
        }
    }
    fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>,
                                   grantResults: IntArray) {
        if (requestCode == REQUEST_CODE) {
            for (i in grantResults.indices) {
                if (grantResults[i] == PackageManager.PERMISSION_GRANTED) {
                    markNeverAskAgainPermission(permissions[i], false)
                } else if (!shouldShowRequestPermissionRationale(permissions[i])) {
                    markNeverAskAgainPermission(permissions[i], true)
                }
            }
            var hasShowRationale = false
            if (!hadShowRationale) {
                hasShowRationale = showRationaleIfNeed()
            }
            if (hadShowRationale || !hasShowRationale) {
                notifyComplete()
            }
        }
    }
    fun onActivityResult(requestCode: Int) {
        if (requestCode == REQUEST_CODE) {
            getPermission(permissions, Status.GRANTED).forEach {
                markNeverAskAgainPermission(it, false)
            }
            notifyComplete()
        }
    }
    fun cancel() {
        notifyComplete()
    }
    private fun doRequestPermission(permissions: Set<String>) {
        activity?.let {
            ActivityCompat.requestPermissions(it, permissions.toTypedArray(), REQUEST_CODE)
        } ?: run {
            fragment?.requestPermissions(permissions.toTypedArray(), REQUEST_CODE)
        }
    }
    private fun getPermission(permissions: Set<String>, status: Status): Set<String> {
        val targetPermissions = HashSet<String>()
        for (p in permissions) {
            when (status) {
                Status.GRANTED -> {
                    if (isPermissionGranted(p)) {
                        targetPermissions.add(p)
                    }
                }
                Status.TEMPORARY_DENIED -> {
                    if (shouldShowRequestPermissionRationale(p)) {
                        targetPermissions.add(p)
                    }
                }
                Status.PERMANENT_DENIED -> {
                    if (isNeverAskAgainPermission(p)) {
                        targetPermissions.add(p)
                    }
                }
                Status.UN_GRANTED -> {
                    if (!isPermissionGranted(p)) {
                        targetPermissions.add(p)
                    }
                }
            }
        }
        return targetPermissions
    }
    private fun isPermissionGranted(permission: String): Boolean {
        return activity?.let {
            ActivityCompat.checkSelfPermission(it, permission) == PackageManager.PERMISSION_GRANTED
        } ?: run {
            ActivityCompat.checkSelfPermission(fragment!!.requireActivity(), permission) == PackageManager.PERMISSION_GRANTED
        }
    }
    private fun shouldShowRequestPermissionRationale(permission: String): Boolean {
        return activity?.let {
            ActivityCompat.shouldShowRequestPermissionRationale(it, permission)
        } ?: run {
            ActivityCompat.shouldShowRequestPermissionRationale(fragment!!.requireActivity(), permission)
        }
    }
    private fun notifyComplete() {
        listener?.onComplete(getPermission(permissions, Status.GRANTED), getPermission(permissions, Status.UN_GRANTED))
    }
    private fun getPrefs(context: Context): SharedPreferences {
        return context.getSharedPreferences("SHARED_PREFS_RUNTIME_PERMISSION", Context.MODE_PRIVATE)
    }
    private fun isNeverAskAgainPermission(permission: String): Boolean {
        return getPrefs(requireContext()).getBoolean(permission, false)
    }
    private fun markNeverAskAgainPermission(permission: String, value: Boolean) {
        getPrefs(requireContext()).edit().putBoolean(permission, value).apply()
    }
    private fun requireContext(): Context {
        return fragment?.requireContext() ?: run {
            activity!!
        }
    }
    enum class Status {
        GRANTED, UN_GRANTED, TEMPORARY_DENIED, PERMANENT_DENIED
    }
    interface Listener {
        fun onComplete(grantedPermissions: Set<String>, deniedPermissions: Set<String>)
        fun onShowPermissionRationale(permissions: Set<String>): Boolean
        fun onShowSettingRationale(permissions: Set<String>): Boolean
    }
    companion object {
        const val REQUEST_CODE = 200
    }
}
Using in Activity like
class MainActivity : AppCompatActivity() {
    private lateinit var smsAndStoragePermissionHandler: RequestPermissionHandler
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        smsAndStoragePermissionHandler = RequestPermissionHandler(this@MainActivity,
                permissions = setOf(Manifest.permission.RECEIVE_SMS, Manifest.permission.READ_EXTERNAL_STORAGE),
                listener = object : RequestPermissionHandler.Listener {
                    override fun onComplete(grantedPermissions: Set<String>, deniedPermissions: Set<String>) {
                        Toast.makeText(this@MainActivity, "complete", Toast.LENGTH_SHORT).show()
                        text_granted.text = "Granted: " + grantedPermissions.toString()
                        text_denied.text = "Denied: " + deniedPermissions.toString()
                    }
                    override fun onShowPermissionRationale(permissions: Set<String>): Boolean {
                        AlertDialog.Builder(this@MainActivity).setMessage("To able to Send Photo, we need SMS and" + " Storage permission")
                                .setPositiveButton("OK") { _, _ ->
                                    smsAndStoragePermissionHandler.retryRequestDeniedPermission()
                                }
                                .setNegativeButton("Cancel") { dialog, _ ->
                                    smsAndStoragePermissionHandler.cancel()
                                    dialog.dismiss()
                                }
                                .show()
                        return true // don't want to show any rationale, just return false here
                    }
                    override fun onShowSettingRationale(permissions: Set<String>): Boolean {
                        AlertDialog.Builder(this@MainActivity).setMessage("Go Settings -> Permission. " + "Make SMS on and Storage on")
                                .setPositiveButton("Settings") { _, _ ->
                                    smsAndStoragePermissionHandler.requestPermissionInSetting()
                                }
                                .setNegativeButton("Cancel") { dialog, _ ->
                                    smsAndStoragePermissionHandler.cancel()
                                    dialog.cancel()
                                }
                                .show()
                        return true
                    }
                })
        button_request.setOnClickListener { handleRequestPermission() }
    }
    private fun handleRequestPermission() {
        smsAndStoragePermissionHandler.requestPermission()
    }
    override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>,
                                            grantResults: IntArray) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
        smsAndStoragePermissionHandler.onRequestPermissionsResult(requestCode, permissions,
                grantResults)
    }
    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        smsAndStoragePermissionHandler.onActivityResult(requestCode)
    }
}
Code on Github 
Demo