Single<String> at rxjava

Question

I want to get an output string from the server with the help of RXJava and RetroFit Reader, but RXJava does not accept the string!

file api:

interface Api { 
    @POST("registerNumber.php")
    fun registerNumber(@Query("phoneNumber") number:String) : Single<String> }

error :

enter image description here

Thank you for your help

Answer 1

I believe that you need to use SingleObserver<String> instead of SingleObserver<Single<String>> as an argument for the subscribe method.