Trying to get post from JsonPlaceHolder by retrofit, but response isn't showing methods

问题

I'm new in retrofit, I'm trying to get single post from jsonplaceholder website, the problem is that I can't find getTitle, getBody, getId, and getUserId in onresponse method in callback. I typed (response.body.) , but getter methods doesn't appear.

MainActivity

public class MainActivity extends AppCompatActivity {

    TextView tvText;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        tvText=findViewById(R.id.tvText);


        Retrofit retrofit= new Retrofit.Builder()
                .baseUrl("https://jsonplaceholder.typicode.com/")
                .addConverterFactory(GsonConverterFactory.create())
                .build();

        ApiInterface apiInterface= retrofit.create(ApiInterface.class);

        Call<POST> call= apiInterface.getPost();

        call.enqueue(new Callback<POST>() {
            @Override
            public void onResponse(Call<POST> call, Response<POST> response) {
                response.body().
            }

            @Override
            public void onFailure(Call<POST> call, Throwable t) {
                Toast.makeText(MainActivity.this, t.getMessage(), Toast.LENGTH_SHORT).show();
            }

        });
    }
}

Interface

public interface ApiInterface {

@GET("posts/1")
Call<POST> getPost();
}

Post class for json keys

public class Post {

    private int id;
    private int userId;
    private String title;
    private String body;

    public int getId() {
        return id;
    }

    public int getUserId() {
        return userId;
    }

    public String getTitle() {
        return title;
    }

    public String getBody() {
        return body;
    }
}

Xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res        /android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">

<TextView
    android:id="@+id/tvText"
    android:layout_width="324dp"
    android:layout_height="92dp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

.....................

回答1:

you need to do small change, the Call type should be Post not POST, as your model class name is Post.

working code

public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_admin);

    Retrofit retrofit= new Retrofit.Builder()
            .baseUrl("https://jsonplaceholder.typicode.com/")
            .addConverterFactory(GsonConverterFactory.create())
            .build();

    ApiInterface apiInterface= retrofit.create(ApiInterface.class);

    Call<Post> call= apiInterface.getPost();

    call.enqueue(new Callback<Post>() {
        @Override
        public void onResponse(Call<Post> call, Response<Post> response) {
            Log.i("response_title",response.body().getTitle()+"");
            Log.i("response_userId",response.body().getUserId()+"");
            Log.i("response_id",response.body().getId()+"");
            Log.i("response_body",response.body().getBody()+"");
        }

        @Override
        public void onFailure(Call<Post> call, Throwable t) {
        }

    });
}

public interface ApiInterface {

    @GET("Posts/1")
    Call<Post> getPost();
}

public class Post {

    private int id;
    private int userId;
    private String title;
    private String body;

    public int getId() {
        return id;
    }

    public int getUserId() {
        return userId;
    }

    public String getTitle() {
        return title;
    }

    public String getBody() {
        return body;
    }
}

}

来源：https://stackoverflow.com/questions/59786697/trying-to-get-post-from-jsonplaceholder-by-retrofit-but-response-isnt-showing