How to pass GET parameters to Retrofit request

Question

I am creating an app with SoundCloud api and trying to append the string value which is entered by user but it showing me null in interface how can I append that in url?

MainActivity.java

  b.setOnClickListener(new View.OnClickListener(){

            @Override
            public void onClick(View p1)
            {
                // TODO: Implement this method
                search = et.getText().toString();
                Log.d("search",search);
                Intent i = new Intent(MainActivity.this, SoundCloud.class);
                i.putExtra("mysearch", search);
                startActivity(i);

                Log.d("CustomUrl",SCService.CustomUrl);
                Toast.makeText(MainActivity.this,""+SCService.CustomUrl,Toast.LENGTH_SHORT).show();


                Retrofit retrofit = new Retrofit.Builder()
                    .baseUrl(Config.API_URL)
                    .addConverterFactory(GsonConverterFactory.create()).build();

                SCService Scservice = retrofit.create(SCService.class);
                Call<Track> call = Scservice.getTrack(search);
                call.enqueue(new Callback<Track>(){

                        @Override
                        public void onResponse(Call<Track> call, Response<Track> response)
                        {
                            // TODO: Implement this method
                            if (response.isSuccessful())
                            {
                                Track track = response.body();
                                streamUrl = track.getStreamUrl();
                                trackname = track.getTitle();
                                Log.e("track", track.getTitle());
                                Toast.makeText(MainActivity.this, trackname, Toast.LENGTH_SHORT).show();
                                Toast.makeText(MainActivity.this, "url" + streamUrl, Toast.LENGTH_SHORT).show();
                                //addToList(trackname);
                            }
                        }

                        @Override
                        public void onFailure(Call<Track> p1, Throwable p2)
                        {
                            // TODO: Implement this method
                            Toast.makeText(MainActivity.this,"error"+p2.getMessage(),Toast.LENGTH_SHORT).show();
                            //showMessage("Network Error: " +  p2.getMessage());
                            Log.d("error", p2.getMessage());
                        }
                    });

            }
        });

ScService.java

public interface SCService
{
    public String CustomUrl = Config.API_URL+"/resolve.json?url="+SoundCloud.SCURL+"&client_id="+Config.CLIENT_ID;
@GET("/resolve.json?url={SCURL}"+"&client_id="+Config.CLIENT_ID)
Call<Track> getTrack(@Path("SCURL")String SCURL);
}       

Searched string is in my SoundCloud.java class

    SCURL = receivedmsg.getString("mysearch");
    Log.d("intentdata",SCURL);

    tv.setText("Search Results for " + SCURL);  

I want append that SCURL String in GET parameter but it showing me null value for SCURL, how could i achieve this?

Update: I have changed my code as above but got this error

enter code here
  03-15 13:22:14.866 6149 6149 D     search com.sk.scdoenloader                   /https://m.soundcloud.com/dharmaworldwide/houseofcards-mixmaster-05b
  03-15 13:22:14.967 6149 6149 D     CustomUrl com.sk.scdoenloader                https://api.soundcloud.com/resolve.json?url=null&client_id=iZIs9mchVcX5lhVRyQGGAYlNPVldzAoX
  03-15 13:22:15.299 6149 6149 E     AndroidRuntime com.sk.scdoenloader                   FATAL EXCEPTION: main
  03-15 13:22:15.299 6149 6149 E     AndroidRuntime com.sk.scdoenloader           Process: com.sk.scdoenloader, PID: 6149
  03-15 13:22:15.299 6149 6149 E     AndroidRuntime com.sk.scdoenloader           java.lang.IllegalArgumentException: No Retrofit annotation found. (parameter #1)
  03-15 13:22:15.299 6149 6149 E     AndroidRuntime com.sk.scdoenloader           for method SCService.getTrack
  03-15 13:22:15.299 6149 6149 E     AndroidRuntime com.sk.scdoenloader           at retrofit2.ServiceMethod$Builder.methodError(ServiceMethod.java:720)
  03-15 13:22:15.299 6149 6149 E     AndroidRuntime com.sk.scdoenloader           at retrofit2.ServiceMethod$Builder.methodError(ServiceMethod.java:711)
  03-15 13:22:15.299 6149 6149 E     AndroidRuntime com.sk.scdoenloader           at retrofit2.ServiceMethod$Builder.parameterError(ServiceMethod.java:729)
  03-15 13:22:15.299 6149 6149 E     AndroidRuntime com.sk.scdoenloader                     

Answer 1

You have to use @Path here

@GET("/resolve.json?url={url}&client_id={clientId}")
Call<Track> getTrack(@Path("url") String url,@Path("clientId") String clientId);

Answer 2

You can use DYNAMIC URL with retrofit !! (With @Get )

public interface SCService{  
   @GET
   public Call<Track> getTrack(@Url String url);
}

Then you can call with your Custom string url

 service.getTrack("/resolve.json?url="+SoundCloud.SCURL+"&client_id="+ Config.CLIENT_ID + SCURL)