hello, chike!

how can I help you today?

Hi Mark

I am fine

and you?

um, OK, I guess

nice. Ok I want help with Retrofit

I can try -- what is the issue?

my backend server sends two different JSON responses, that is the user object if successful and error message if failure

how can I handle that

since Retrofit allows just one

well, there are two issues: data types, and JSON parsers

the Retrofit code will be expecting a single return type

you would need to pick some common ancestor of your possible responses

that could be java.lang.Object, if needed

but then you probably will need to create a custom converter factory to handle detecting what sort of JSON you got and routing Gson (or whatever) to parse it appropriately, returning the right actual value

ok. Can I get a simple example of that please

sorry, I have never done that

I am making educated guesses based on my knowledge of Retrofit

ok

ideally, the JSON you got back would be something that wrapped either the user object or the error message

yes

{"user": {...}} or {"error":"..."}

in that case, you could model the response as a UserOrError object, with user and error fields

and then deal with one or the other being null

I think that will be good

thanks Mark

you're welcome!