Retrofit2设置返回类型是字符串（String）类型

之前返回的是对象，但是我想看看返回的字符串。

之前的代码：

package com.example.z.study;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.ImageView;
import android.widget.TextView;

import com.google.gson.Gson;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;
import retrofit2.converter.scalars.ScalarsConverterFactory;
import retrofit2.http.GET;
import retrofit2.http.Query;

public class MainActivity extends AppCompatActivity {

    @BindView(R.id.imageView)
    ImageView imageView;
    Animation animation;
    @BindView(R.id.tv_rx)
    TextView tvRx;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.content_main);
        ButterKnife.bind(this);
        animation = AnimationUtils.loadAnimation(this, R.anim.demo);
    }

    @OnClick(R.id.btn_anim)
    public void setBtnAnim() {
        imageView.startAnimation(animation);
    }

    @OnClick(R.id.btn_rx)
    public void btn_rx() {
        getString();
    }

    public void getString() {
        String baseUrl = "https://api.douban.com/v2/movie/";

        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(baseUrl)
                .addConverterFactory(GsonConverterFactory.create())//转为对象类型
                .build();


        MovieService movieService = retrofit.create(MovieService.class);
        Call<MovieVo> call = movieService.getTopMovie(0, 10);
        call.enqueue(new Callback<MovieVo>() {
            @Override
            public void onResponse(Call<MovieVo> call, Response<MovieVo> response) {


                tvRx.setText(response.body().toString());
                System.out.println("**********" + response.body());
                Gson gson = new Gson();
            }

            @Override
            public void onFailure(Call<MovieVo> call, Throwable throwable) {
                System.out.println("--------------------");
                tvRx.setText(throwable.getMessage());
            }
        });
    }

    public interface MovieService {

        @GET("top250")
        Call<MovieVo> getTopMovie(@Query("start") int start, @Query("count") int count);
    }
}

Gradle:

apply plugin: 'com.android.application'

android {
    compileSdkVersion 25
    buildToolsVersion "25.0.3"
    defaultConfig {
        applicationId "com.example.z.study"
        minSdkVersion 18
        targetSdkVersion 25
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:25.3.1'
    compile 'com.android.support:design:25.3.1'
    compile 'com.android.support.constraint:constraint-layout:1.0.1'
    testCompile 'junit:junit:4.12'

//    // https://mvnrepository.com/artifact/io.reactivex.rxjava2/rxjava
//    compile group: 'io.reactivex.rxjava2', name: 'rxjava', version: '2.1.0'
//// https://mvnrepository.com/artifact/io.reactivex.rxjava2/rxandroid
//    compile group: 'io.reactivex.rxjava2', name: 'rxandroid', version: '2.0.1'


    compile 'io.reactivex:rxjava:1.1.0'
    compile 'io.reactivex:rxandroid:1.1.0'

// https://mvnrepository.com/artifact/com.squareup.retrofit2/retrofit
    compile group: 'com.squareup.retrofit2', name: 'retrofit', version: '2.3.0'
// https://mvnrepository.com/artifact/com.squareup.retrofit2/converter-gson
    compile group: 'com.squareup.retrofit2', name: 'converter-gson', version: '2.3.0'


// https://mvnrepository.com/artifact/com.squareup.retrofit2/adapter-rxjava
    compile group: 'com.squareup.retrofit2', name: 'adapter-rxjava', version: '2.3.0'
// https://mvnrepository.com/artifact/com.google.code.gson/gson
    compile group: 'com.google.code.gson', name: 'gson', version: '2.8.1'
// https://mvnrepository.com/artifact/com.jakewharton/butterknife
    compile group: 'com.jakewharton', name: 'butterknife', version: '8.6.0'
    annotationProcessor 'com.jakewharton:butterknife-compiler:8.6.0'

}

现在的代码：

package com.example.z.study;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.ImageView;
import android.widget.TextView;

import com.google.gson.Gson;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;
import retrofit2.converter.scalars.ScalarsConverterFactory;
import retrofit2.http.GET;
import retrofit2.http.Query;

public class MainActivity extends AppCompatActivity {

    @BindView(R.id.imageView)
    ImageView imageView;
    Animation animation;
    @BindView(R.id.tv_rx)
    TextView tvRx;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.content_main);
        ButterKnife.bind(this);
        animation = AnimationUtils.loadAnimation(this, R.anim.demo);
    }

    @OnClick(R.id.btn_anim)
    public void setBtnAnim() {
        imageView.startAnimation(animation);
    }

    @OnClick(R.id.btn_rx)
    public void btn_rx() {
        getString();
    }

    public void getString() {
        String baseUrl = "https://api.douban.com/v2/movie/";

        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(baseUrl)
                .addConverterFactory(ScalarsConverterFactory.create())
                .build();


        MovieService movieService = retrofit.create(MovieService.class);
        Call<String> call = movieService.getTopMovie(0, 10);
        call.enqueue(new Callback<String>() {
            @Override
            public void onResponse(Call<String> call, Response<String> response) {


                tvRx.setText(response.body().toString());
                System.out.println("**********" + response.body());
                Gson gson = new Gson();
            }

            @Override
            public void onFailure(Call<String> call, Throwable throwable) {
                System.out.println("--------------------");
                tvRx.setText(throwable.getMessage());
            }
        });
    }

    public interface MovieService {

        @GET("top250")
        Call<String> getTopMovie(@Query("start") int start, @Query("count") int count);
    }
}

Gradle:

apply plugin: 'com.android.application'

android {
    compileSdkVersion 25
    buildToolsVersion "25.0.3"
    defaultConfig {
        applicationId "com.example.z.study"
        minSdkVersion 18
        targetSdkVersion 25
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:25.3.1'
    compile 'com.android.support:design:25.3.1'
    compile 'com.android.support.constraint:constraint-layout:1.0.1'
    testCompile 'junit:junit:4.12'

//    // https://mvnrepository.com/artifact/io.reactivex.rxjava2/rxjava
//    compile group: 'io.reactivex.rxjava2', name: 'rxjava', version: '2.1.0'
//// https://mvnrepository.com/artifact/io.reactivex.rxjava2/rxandroid
//    compile group: 'io.reactivex.rxjava2', name: 'rxandroid', version: '2.0.1'


    compile 'io.reactivex:rxjava:1.1.0'
    compile 'io.reactivex:rxandroid:1.1.0'

// https://mvnrepository.com/artifact/com.squareup.retrofit2/retrofit
    compile group: 'com.squareup.retrofit2', name: 'retrofit', version: '2.3.0'
// https://mvnrepository.com/artifact/com.squareup.retrofit2/converter-gson
    compile group: 'com.squareup.retrofit2', name: 'converter-gson', version: '2.3.0'
    // https://mvnrepository.com/artifact/com.squareup.retrofit2/converter-scalars
    compile group: 'com.squareup.retrofit2', name: 'converter-scalars', version: '2.3.0'

// https://mvnrepository.com/artifact/com.squareup.retrofit2/adapter-rxjava
    compile group: 'com.squareup.retrofit2', name: 'adapter-rxjava', version: '2.3.0'
// https://mvnrepository.com/artifact/com.google.code.gson/gson
    compile group: 'com.google.code.gson', name: 'gson', version: '2.8.1'
// https://mvnrepository.com/artifact/com.jakewharton/butterknife
    compile group: 'com.jakewharton', name: 'butterknife', version: '8.6.0'
    annotationProcessor 'com.jakewharton:butterknife-compiler:8.6.0'

}