اندروید Dagger 2 + Retrofit + RecyclerView

public class A {
 
public static void main(String[] args){
B b = new B();
C c = new C(b);
D d = new D(b, c);
E e = new E(d, b);
 
A a = new A(e, b);
}

implementation 'com.android.support:design:27.1.0'
implementation group: 'com.google.code.gson', name: 'gson', version: '2.8.2'
implementation group: 'com.squareup.retrofit2', name: 'converter-gson', version: '2.3.0'
implementation group: 'com.squareup.okhttp3', name: 'okhttp', version: '3.10.0'
implementation group: 'com.squareup.okhttp3', name: 'logging-interceptor', version: '3.9.0'
implementation group: 'com.google.code.gson', name: 'gson', version: '2.8.2'
implementation(group: 'com.squareup.retrofit2', name: 'retrofit', version: '2.3.0') {
exclude module: 'okhttp'
}
 
implementation 'com.google.dagger:dagger-android:2.11'
implementation 'com.google.dagger:dagger-android-support:2.11'
annotationProcessor 'com.google.dagger:dagger-android-processor:2.11'
annotationProcessor 'com.google.dagger:dagger-compiler:2.13'

package com.journaldev.dagger2retrofitrecyclerview.di.scopes;
 
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import javax.inject.Scope;
 
@Scope
@Retention(RetentionPolicy.CLASS)
public @interface ActivityScope {
}

package com.journaldev.dagger2retrofitrecyclerview.di.scopes;
 
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import javax.inject.Scope;
 
@Scope
@Retention(RetentionPolicy.CLASS)
public @interface ApplicationScope {
}

package com.journaldev.dagger2retrofitrecyclerview.di.qualifier;
 
import javax.inject.Qualifier;
 
@Qualifier
public @interface ApplicationContext {
 
}

package com.journaldev.dagger2retrofitrecyclerview.di.module;
 
import android.content.Context;
 
import com.journaldev.dagger2retrofitrecyclerview.di.qualifier.ApplicationContext;
import com.journaldev.dagger2retrofitrecyclerview.di.scopes.ApplicationScope;
 
import dagger.Module;
import dagger.Provides;
 
@Module
public class ContextModule {
private Context context;
 
public ContextModule(Context context) {
this.context = context;
}
 
@Provides
@ApplicationScope
@ApplicationContext
public Context provideContext() {
return context;
}
}

package com.journaldev.dagger2retrofitrecyclerview.di.module;
 
import com.journaldev.dagger2retrofitrecyclerview.di.scopes.ApplicationScope;
import com.journaldev.dagger2retrofitrecyclerview.retrofit.APIInterface;
 
import dagger.Module;
import dagger.Provides;
import okhttp3.OkHttpClient;
import okhttp3.logging.HttpLoggingInterceptor;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;
 
@Module
public class RetrofitModule {
 
@Provides
@ApplicationScope
APIInterface getApiInterface(Retrofit retroFit) {
return retroFit.create(APIInterface.class);
}
 
@Provides
@ApplicationScope
Retrofit getRetrofit(OkHttpClient okHttpClient) {
return new Retrofit.Builder()
.baseUrl("https://swapi.co/api/")
.addConverterFactory(GsonConverterFactory.create())
.client(okHttpClient)
.build();
}
 
@Provides
@ApplicationScope
OkHttpClient getOkHttpCleint(HttpLoggingInterceptor httpLoggingInterceptor) {
return new OkHttpClient.Builder()
.addInterceptor(httpLoggingInterceptor)
.build();
}
 
@Provides
@ApplicationScope
HttpLoggingInterceptor getHttpLoggingInterceptor() {
HttpLoggingInterceptor httpLoggingInterceptor = new HttpLoggingInterceptor();
httpLoggingInterceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
return httpLoggingInterceptor;
}
}

package com.journaldev.dagger2retrofitrecyclerview.di.module;
 
import android.content.Context;
 
import com.journaldev.dagger2retrofitrecyclerview.di.qualifier.ActivityContext;
import com.journaldev.dagger2retrofitrecyclerview.di.scopes.ActivityScope;
import com.journaldev.dagger2retrofitrecyclerview.ui.MainActivity;
 
import dagger.Module;
import dagger.Provides;
 
@Module
public class MainActivityContextModule {
private MainActivity mainActivity;
 
public Context context;
 
public MainActivityContextModule(MainActivity mainActivity) {
this.mainActivity = mainActivity;
context = mainActivity;
}
 
@Provides
@ActivityScope
public MainActivity providesMainActivity() {
return mainActivity;
}
 
@Provides
@ActivityScope
@ActivityContext
public Context provideContext() {
return context;
}
 
}

 
import com.journaldev.dagger2retrofitrecyclerview.adapter.RecyclerViewAdapter;
import com.journaldev.dagger2retrofitrecyclerview.di.scopes.ActivityScope;
import com.journaldev.dagger2retrofitrecyclerview.ui.MainActivity;
 
import dagger.Module;
import dagger.Provides;
 
@Module(includes = {MainActivityContextModule.class})
public class AdapterModule {
 
@Provides
@ActivityScope
public RecyclerViewAdapter getStarWarsPeopleLIst(RecyclerViewAdapter.ClickListener clickListener) {
return new RecyclerViewAdapter(clickListener);
}
 
@Provides
@ActivityScope
public RecyclerViewAdapter.ClickListener getClickListener(MainActivity mainActivity) {
return mainActivity;
}
}

برای ایجاد RecyclerViewAdapter از داده های POJO استفاده می شود.

همچنین ، ClickListener یک interface است که در کلاس RecyclerViewAdapter تعریف شده است تا متدهای  پاسخ به callback click listener را از خود Activity ایجاد کند.

این وابستگی MainActivity را تزریق می کند زیرا ما MainActivityContextModule را در تعریف گنجانده ایم.

بیایید به کلاسهای APIInterface و POJO نگاهی بیندازیم.

کد کلاس APIInterface.java در زیر آورده شده است.

package com.journaldev.dagger2retrofitrecyclerview.retrofit;
 
import com.journaldev.dagger2retrofitrecyclerview.pojo.Film;
import com.journaldev.dagger2retrofitrecyclerview.pojo.StarWars;
 
import retrofit2.Call;
import retrofit2.http.GET;
import retrofit2.http.Query;
import retrofit2.http.Url;
 
public interface APIInterface {
 
@GET("people/?")
Call<StarWars> getPeople(@Query("format") String format);
 
@GET
Call<Film> getFilmData(@Url String url, @Query("format") String format);
}

package com.journaldev.dagger2retrofitrecyclerview.pojo;
 
import com.google.gson.annotations.SerializedName;
import java.util.List;
 
public class StarWars {
 
@SerializedName("results")
public List<People> results = null;
 
public class People {
 
@SerializedName("name")
public String name;
@SerializedName("height")
public String height;
@SerializedName("mass")
public String mass;
@SerializedName("birth_year")
public String birthYear;
@SerializedName("gender")
public String gender;
@SerializedName("homeworld")
public String homeworld;
@SerializedName("films")
public List<String> films = null;
}
}

package com.journaldev.dagger2retrofitrecyclerview.pojo;
 
import com.google.gson.annotations.SerializedName;
 
public class Film {
 
@SerializedName("title")
public String title;
@SerializedName("director")
public String director;
 
}

package com.journaldev.dagger2retrofitrecyclerview.di.component;
 
import android.content.Context;
 
import com.journaldev.dagger2retrofitrecyclerview.MyApplication;
import com.journaldev.dagger2retrofitrecyclerview.di.module.ContextModule;
import com.journaldev.dagger2retrofitrecyclerview.di.module.RetrofitModule;
import com.journaldev.dagger2retrofitrecyclerview.di.qualifier.ApplicationContext;
import com.journaldev.dagger2retrofitrecyclerview.di.scopes.ApplicationScope;
import com.journaldev.dagger2retrofitrecyclerview.retrofit.APIInterface;
 
import dagger.Component;
 
@ApplicationScope
@Component(modules = {ContextModule.class, RetrofitModule.class})
public interface ApplicationComponent {
 
public APIInterface getApiInterface();
 
@ApplicationContext
public Context getContext();
 
public void injectApplication(MyApplication myApplication);
}

package com.journaldev.dagger2retrofitrecyclerview.di.component;
 
import android.content.Context;
 
import com.journaldev.dagger2retrofitrecyclerview.di.module.AdapterModule;
import com.journaldev.dagger2retrofitrecyclerview.di.qualifier.ActivityContext;
import com.journaldev.dagger2retrofitrecyclerview.di.scopes.ActivityScope;
import com.journaldev.dagger2retrofitrecyclerview.ui.MainActivity;
 
import dagger.Component;
 
@ActivityScope
@Component(modules = AdapterModule.class, dependencies = ApplicationComponent.class)
public interface MainActivityComponent {
 
@ActivityContext
Context getContext();
 
void injectMainActivity(MainActivity mainActivity);
}

package com.journaldev.dagger2retrofitrecyclerview.di.component;
 
import com.journaldev.dagger2retrofitrecyclerview.di.scopes.ActivityScope;
import com.journaldev.dagger2retrofitrecyclerview.ui.DetailActivity;
import dagger.Component;
 
@Component(dependencies = ApplicationComponent.class)
@ActivityScope
public interface DetailActivityComponent {
 
void inject(DetailActivity detailActivity);
}

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="https://schemas.android.com/apk/res/android"
    xmlns:app="https://schemas.android.com/apk/res-auto"
    xmlns:tools="https://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".ui.MainActivity">
 
    <android.support.v7.widget.RecyclerView
        android:id="@+id/recyclerView"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
 
</android.support.constraint.ConstraintLayout>

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="https://schemas.android.com/apk/res/android"
    xmlns:app="https://schemas.android.com/apk/res-auto"
    xmlns:tools="https://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".ui.DetailActivity">
 
    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Loading..."
        android:textColor="@android:color/black"
        android:textSize="28sp"
        android:gravity="center"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
 
</android.support.constraint.ConstraintLayout>

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="https://schemas.android.com/apk/res/android"
    xmlns:app="https://schemas.android.com/apk/res-auto"
    android:id="@+id/constraintLayout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="16dp">
 
    <TextView
        android:id="@+id/txtName"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
 
    <TextView
        android:id="@+id/txtBirthYear"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_constraintTop_toBottomOf="@+id/txtName" />
 
</android.support.constraint.ConstraintLayout>

package com.journaldev.dagger2retrofitrecyclerview;
 
import android.app.Activity;
import android.app.Application;
 
import com.journaldev.dagger2retrofitrecyclerview.di.component.ApplicationComponent;
import com.journaldev.dagger2retrofitrecyclerview.di.component.DaggerApplicationComponent;
import com.journaldev.dagger2retrofitrecyclerview.di.module.ContextModule;
 
public class MyApplication extends Application {
 
ApplicationComponent applicationComponent;
 
@Override
public void onCreate() {
super.onCreate();
 
applicationComponent = DaggerApplicationComponent.builder().contextModule(new ContextModule(this)).build();
applicationComponent.injectApplication(this);
 
}
 
public static MyApplication get(Activity activity){
return (MyApplication) activity.getApplication();
}
 
public ApplicationComponent getApplicationComponent() {
return applicationComponent;
}
}

package com.journaldev.dagger2retrofitrecyclerview.ui;
 
import android.content.Context;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.widget.Toast;
 
import com.journaldev.dagger2retrofitrecyclerview.MyApplication;
import com.journaldev.dagger2retrofitrecyclerview.R;
import com.journaldev.dagger2retrofitrecyclerview.adapter.RecyclerViewAdapter;
import com.journaldev.dagger2retrofitrecyclerview.di.component.ApplicationComponent;
import com.journaldev.dagger2retrofitrecyclerview.di.component.DaggerMainActivityComponent;
import com.journaldev.dagger2retrofitrecyclerview.di.component.MainActivityComponent;
import com.journaldev.dagger2retrofitrecyclerview.di.module.MainActivityContextModule;
import com.journaldev.dagger2retrofitrecyclerview.di.qualifier.ActivityContext;
import com.journaldev.dagger2retrofitrecyclerview.di.qualifier.ApplicationContext;
import com.journaldev.dagger2retrofitrecyclerview.pojo.StarWars;
import com.journaldev.dagger2retrofitrecyclerview.retrofit.APIInterface;
 
import java.util.List;
 
import javax.inject.Inject;
 
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
 
public class MainActivity extends AppCompatActivity implements RecyclerViewAdapter.ClickListener {
 
    private RecyclerView recyclerView;
    MainActivityComponent mainActivityComponent;
 
    @Inject
    public RecyclerViewAdapter recyclerViewAdapter;
 
    @Inject
    public APIInterface apiInterface;
 
    @Inject
    @ApplicationContext
    public Context mContext;
 
    @Inject
    @ActivityContext
    public Context activityContext;
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
        recyclerView = findViewById(R.id.recyclerView);
        recyclerView.setLayoutManager(new LinearLayoutManager(MainActivity.this));
 
        ApplicationComponent applicationComponent = MyApplication.get(this).getApplicationComponent();
        mainActivityComponent = DaggerMainActivityComponent.builder()
                .mainActivityContextModule(new MainActivityContextModule(this))
                .applicationComponent(applicationComponent)
                .build();
 
        mainActivityComponent.injectMainActivity(this);
        recyclerView.setAdapter(recyclerViewAdapter);
 
        apiInterface.getPeople("json").enqueue(new Callback<StarWars>() {
            @Override
            public void onResponse(Call<StarWars> call, Response<StarWars> response) {
                populateRecyclerView(response.body().results);
            }
 
            @Override
            public void onFailure(Call<StarWars> call, Throwable t) {
 
            }
        });
    }
 
    private void populateRecyclerView(List<StarWars.People> response) {
        recyclerViewAdapter.setData(response);
    }
 
 
    @Override
    public void launchIntent(String url) {
        Toast.makeText(mContext, "RecyclerView Row selected", Toast.LENGTH_SHORT).show();
        startActivity(new Intent(activityContext, DetailActivity.class).putExtra("url", url));
    }
}

package com.journaldev.dagger2retrofitrecyclerview.adapter;
 
import android.support.constraint.ConstraintLayout;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
 
import com.journaldev.dagger2retrofitrecyclerview.R;
import com.journaldev.dagger2retrofitrecyclerview.pojo.StarWars;
 
import java.util.ArrayList;
import java.util.List;
 
import javax.inject.Inject;
 
 
public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.ViewHolder> {
    private List<StarWars.People> data;
    private RecyclerViewAdapter.ClickListener clickListener;
 
    @Inject
    public RecyclerViewAdapter(ClickListener clickListener) {
        this.clickListener = clickListener;
        data = new ArrayList<>();
    }
 
    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        return new ViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.recycler_view_list_row, parent, false));
    }
 
    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        holder.txtName.setText(data.get(position).name);
        holder.txtBirthYear.setText(data.get(position).birthYear);
    }
 
    @Override
    public int getItemCount() {
        return data.size();
    }
 
    class ViewHolder extends RecyclerView.ViewHolder {
 
        private TextView txtName;
        private TextView txtBirthYear;
        private ConstraintLayout constraintLayoutContainer;
 
        ViewHolder(View itemView) {
            super(itemView);
 
            txtName = itemView.findViewById(R.id.txtName);
            txtBirthYear = itemView.findViewById(R.id.txtBirthYear);
            constraintLayoutContainer = itemView.findViewById(R.id.constraintLayout);
 
            constraintLayoutContainer.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    clickListener.launchIntent(data.get(getAdapterPosition()).films.get(0));
                }
            });
        }
    }
 
    public interface ClickListener {
        void launchIntent(String filmName);
    }
 
    public void setData(List<StarWars.People> data) {
        this.data.addAll(data);
        notifyDataSetChanged();
    }
}

package com.journaldev.dagger2retrofitrecyclerview.ui;
 
import android.content.Context;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.TextView;
 
import com.journaldev.dagger2retrofitrecyclerview.MyApplication;
import com.journaldev.dagger2retrofitrecyclerview.R;
import com.journaldev.dagger2retrofitrecyclerview.di.component.ApplicationComponent;
import com.journaldev.dagger2retrofitrecyclerview.di.component.DaggerDetailActivityComponent;
import com.journaldev.dagger2retrofitrecyclerview.di.component.DetailActivityComponent;
import com.journaldev.dagger2retrofitrecyclerview.di.qualifier.ApplicationContext;
import com.journaldev.dagger2retrofitrecyclerview.pojo.Film;
import com.journaldev.dagger2retrofitrecyclerview.retrofit.APIInterface;
 
import javax.inject.Inject;
 
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
 
public class DetailActivity extends AppCompatActivity {
 
    DetailActivityComponent detailActivityComponent;
 
    @Inject
    public APIInterface apiInterface;
 
    @Inject
    @ApplicationContext
    public Context mContext;
 
    TextView textView;
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_detail);
 
        textView = findViewById(R.id.textView);
 
        String url = getIntent().getStringExtra("url");
 
        ApplicationComponent applicationComponent = MyApplication.get(this).getApplicationComponent();
        detailActivityComponent = DaggerDetailActivityComponent.builder()
                .applicationComponent(applicationComponent)
                .build();
 
        detailActivityComponent.inject(this);
 
        apiInterface.getFilmData(url, "json").enqueue(new Callback<Film>() {
            @Override
            public void onResponse(Call<Film> call, Response<Film> response) {
                Film films = response.body();
                String text = "Film name:\n" + films.title + "\nDirector:\n" + films.director;
                textView.setText(text);
            }
 
            @Override
            public void onFailure(Call<Film> call, Throwable t) {
 
            }
        });
    }
}