Attribute must be constant in Retrofit @Header

Question

I want to pass a header to each POST request in a retrofit api . Since i have lots of methods hear, i can't copy/paste the header information for every method.

public interface ApiInterface {
    String[] header = {"Accept:application/json",
                       "apiKey:12345",
                       "Content-Type:application/json"};

    @Headers(header)
    @POST("signup?")
    Call<SignupResponse> createUser(@Body SignupData signupData);

    @Headers(header)
    @POST("another")
    ....
}

The header variable in @HEADER creates this error:

Attribute must be constant

How can i solve the problem?

Is there any problem if you remove, `Accept` and `Content-Type` part? Just try with `@Header()` which requires `String` type not `String[]` use ("apiKey:12345"). And also why don't you try Retrofit's [HttpInterceptor](https://stackoverflow.com/a/35024248/5180017)? — Shashanth, Nov 10 '19 at 15:27
The **SOLUTION** was the link which @Shashanth recommended. I should use the HttpClient interceptor to add headers to retrofit obj. — Ehsan Toghian, Nov 11 '19 at 07:44

score 2 · Answer 1 · answered Nov 10 '19 at 13:38

2

Try this

@Headers({"Accept:application/json",
            "apiKey:12345",
            "Content-Type:application/json"})
@POST("signup?")
    Call<SignupResponse> createUser(@Body SignupData signupData);

answered Nov 10 '19 at 13:38

Rajnish suryavanshi

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Actually i want to avoid write the 3 lines in `@Headers()` for each method. is it possible? – Ehsan Toghian Nov 10 '19 at 13:50
There is no alternative. – Rajnish suryavanshi Nov 10 '19 at 13:55

CommonsWare · Answer 2 · 2019-11-10T13:49:25.337

1

Use:

@Headers({"Accept:application/json",
         "apiKey:12345",
         "Content-Type:application/json"})
@POST("another")

See the "Header Manipulation" section of the Retrofit documentation.

edited Nov 10 '19 at 13:49

answered Nov 10 '19 at 13:38

CommonsWare

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Attribute must be constant in Retrofit @Header

2 Answers2