前言

我們在開始一個新專案的時候，肯定會涉及到一些通用工具的使用，比如一些util工具類、圖片載入庫、網路請求庫等。本篇博文就是對這些通用工具類的一些封裝，這樣可以節省很多開發時間。下面就以Retrofit的封裝為例向大家介紹如何使用這些library。

Api

public class Api {

    private static final int TIME_OUT = 10000;
    private static final Map<String, Object> mServiceMap = new HashMap<>();

    private
 
 Api() {
    }

    public <S> S getService(Class<S> serviceClass) {
        String className = serviceClass.getName();
        if (!(mServiceMap.containsKey(className))) {
            throw new RuntimeException("You must init " + className + " first when application init !");
        }
        return
 
 (S) mServiceMap.get(className);
    }

    public <S> void init(Class<S> serviceClass, String baseUrl, OkHttpClient client) {
        if (client == null) {
            client = new OkHttpClient.Builder()
                    .connectTimeout(TIME_OUT, TimeUnit.MILLISECONDS)
                    .writeTimeout(TIME_OUT, TimeUnit.MILLISECONDS)
                    .readTimeout(TIME_OUT, TimeUnit.MILLISECONDS)
                    .build();
        }
        if
 
 (baseUrl == null || TextUtils.isEmpty(baseUrl)) {
            throw new NullPointerException("baseUrl can not be null");
        }
        if (!baseUrl.endsWith("/")) {
            throw new IllegalArgumentException("baseUrl must be end with /");
        }
        createService(serviceClass, baseUrl, client);
    }

    public static Api getInstance() {
        return SingleHolder.API_INSTANCE;
    }

    private static class SingleHolder {
        private static final Api API_INSTANCE = new Api();
    }

    private <S> void createService(Class<S> serviceClass, String baseUrl, OkHttpClient client) {
        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl(baseUrl)
                .addConverterFactory(GsonConverterFactory.create())
                .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                .client(client)
                .build();
        S service = retrofit.create(serviceClass);
        mServiceMap.put(serviceClass.getName(), service);
    }
}

開始使用

目錄結構

引用方式

1. library

• Import Module
  
  
• 新增依賴
  在build.gradle檔案中新增依賴

implementation project(':apilibrary')

2. aar檔案

• 編譯apilibrary庫生成aar檔案
  

• 複製aar檔案到專案libs資料夾下
  

• 在build.gradle檔案中新增依賴
  根目錄下新增

repositories {
    flatDir {
        dirs 'libs'
    }
}

dependencies下新增

implementation(name: 'apilibrary-release', ext: 'aar')

開始使用

• 新增依賴
  

  這裡我們需要在專案的app目錄下的build.gradle檔案中引入apilibrary中使用到的庫，比如Retrofit、RxJava。

implementation 'com.squareup.retrofit2:retrofit:2.3.0'
implementation 'com.squareup.retrofit2:converter-gson:2.3.0'
implementation 'com.squareup.retrofit2:adapter-rxjava2:2.2.0'
implementation 'io.reactivex.rxjava2:rxjava:2.1.3'
implementation 'io.reactivex.rxjava2:rxandroid:2.0.1'

• 建立ApiService
  

  建立ApiService用於存放我們的請求方法。

public interface ApiService {
    //模擬方法，根據實際網路請求新增
    @GET("category/query")
    Observable<DataResponse> getData(@Query("key") String key);
}

• Application中初始化apilibrary
  

  這裡base url和client根據專案需求定義。

public class ProjectApplication extends Application {

    private static final String BASE_URL = "http://base.url/";
    private OkHttpClient client = new OkHttpClient.Builder()
            .build();

    @Override
    public void onCreate() {
        super.onCreate();
        Api.getInstance().init(ApiService.class, BASE_URL, client);
    }
}

使用MVP模式載入資料

• 建立DataView繼承BaseView

public interface DataView extends BaseView<DataResponse> {
}

• 建立DataPresenter繼承BasePresenter

public class DataPresenter implements BasePresenter<DataView> {

    private DataView mView;

    @Override
    public void attachView(DataView dataView) {
        mView = dataView;
    }

    @Override
    public void detachView() {
        mView = null;
    }
}

• Activity實現DataView介面並初始化DataPresenter

public class MainActivity extends AppCompatActivity implements DataView {

    private DataPresenter mPresenter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mPresenter = new DataPresenter();
        mPresenter.attachView(this);
    }

    @Override
    public Context getMyContext() {
        return this;
    }

    @Override
    public void onError(Throwable throwable) {
        //異常錯誤處理
    }

    @Override
    public void showProgress() {
        //顯示載入dialog
    }

    @Override
    public void dismissProgress() {
        //消失dialog
    }

    @Override
    public void setData(DataResponse dataResponse) {
        //展示資料
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        //Activity銷燬時取消網路請求
        if (mPresenter != null) {
            mPresenter.detachView();
        }
    }
}

• DataPresenter中請求資料

public class DataPresenter implements BasePresenter<DataView> {

    private DataView mView;
    private Disposable mDataDisposable;

    @Override
    public void attachView(DataView dataView) {
        mView = dataView;
    }

    @Override
    public void detachView() {
        mView = null;
        if (mDataDisposable != null) {
            mDataDisposable.dispose();
        }
    }

    public void getData() {
        if (mView == null) {
            return;
        }
        mView.showProgress();
        Api.getInstance().getService(ApiService.class)
                .getData("key")
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Observer<DataResponse>() {
                    @Override
                    public void onSubscribe(Disposable d) {
                        mDataDisposable = d;
                    }

                    @Override
                    public void onNext(DataResponse dataResponse) {
                        if (mView != null) {
                            //資料載入回撥
                            mView.setData(dataResponse);
                        }
                    }

                    @Override
                    public void onError(Throwable e) {
                        if (mView != null) {
                            mView.onError(e);
                            mView.dismissProgress();
                        }
                    }

                    @Override
                    public void onComplete() {
                        if (mDataDisposable != null) {
                            mDataDisposable.dispose();
                        }
                        if (mView != null) {
                            mView.dismissProgress();
                        }
                    }
                });

    }
}

• MainActivity中請求資料

mPresenter.getData();

專案混淆

如果你的專案需要混淆處理的話，需要在proguard-rules.pro檔案中新增以下配置。

-keep class com.kxg.apilibrary.**{*;}

# RxJava and RxAndroid
-dontwarn sun.misc.**

-keepclassmembers class rx.internal.util.unsafe.*ArrayQueue*Field* {
   long producerIndex;
   long consumerIndex;
}

-keepclassmembers class rx.internal.util.unsafe.BaseLinkedQueueProducerNodeRef {
    rx.internal.util.atomic.LinkedQueueNode producerNode;
}

-keepclassmembers class rx.internal.util.unsafe.BaseLinkedQueueConsumerNodeRef {
    rx.internal.util.atomic.LinkedQueueNode consumerNode;
}

# OkHttp3
-dontwarn okhttp3.**
-dontwarn okio.**
-dontwarn javax.annotation.**
-dontwarn org.conscrypt.**
# A resource is loaded with a relative path so the package of this class must be preserved.
-keepnames class okhttp3.internal.publicsuffix.PublicSuffixDatabase

# Retrofit
-dontwarn retrofit2.**
-keep class retrofit2.** { *; }
-keepattributes Signature

# Gson
-keep class com.google.gson.stream.** { *; }
-keepattributes EnclosingMethod

多base url支援

• 如果你的專案有多個base url的話，apilibrary也同樣支援，只不過你需要再建立一個ApiService2。

public interface ApiService2 {
}

• 同樣的在Application中初始化，其請求使用步驟和上面介紹的ApiService是一樣的。

public class ProjectApplication extends Application {

    private static final String BASE_URL = "http://base.url";
    private OkHttpClient client = new OkHttpClient.Builder()
            .build();

    private static final String ANOTHER_BASE_URL = "http://another.base.url";

    @Override
    public void onCreate() {
        super.onCreate();
        Api.getInstance().init(ApiService.class, BASE_URL, client);

        Api.getInstance().init(ApiService2.class, ANOTHER_BASE_URL, client);
    }
}

總結

以上就是關於Retrofit的相關封裝，並結合MVP模式演示了請求示例，希望你可以用到你的專案中，如整合遇到問題的話可留言或郵件[email protected]。

util-project原始碼下載