rxjava+retrofit实例解析

首先看下retrofit定义的接口：

1.ZhuangbiApi .class

public interface ZhuangbiApi {
    @GET("search")
    Observable<List<ZhuangbiImage>> search(@Query("q") String query);
}

解释：get请求，baseurl后拼接search，后面跟上 ?q= 的形式(注：Query后自带?)
如：https://www.zhuangbi.info/search?q=110

2.GankApi .class

public interface GankApi {
    @GET("data/福利/{number}/{page}")
    Observable<GankBeautyResult> getBeauties(@Path("number") int number, @Path("page") int page);
}

解释：get请求，拼接data/福利/{number}/{page}，其中，@GET中的{number}会由下面getBeauties参数的number替代，page同理，（注：Path的用法和Query区分）
如：https://www.zhuangbi.info/data/福利/110/1

3.FakeApi .class

// (c)2016 Flipboard Inc, All Rights Reserved.

package com.rengwuxian.rxjavasamples.network.api;

import android.support.annotation.NonNull;

import com.rengwuxian.rxjavasamples.model.FakeThing;
import com.rengwuxian.rxjavasamples.model.FakeToken;

import java.util.Random;

import io.reactivex.Observable;
import io.reactivex.functions.Function;

public class FakeApi {
    Random random = new Random();

    public Observable<FakeToken> getFakeToken(@NonNull String fakeAuth) {
        return Observable.just(fakeAuth)
                .map(new Function<String, FakeToken>() {
                    @Override
                    public FakeToken apply(String fakeAuth) {
                        // Add some random delay to mock the network delay
                        int fakeNetworkTimeCost = random.nextInt(500) + 500;
                        try {
                            Thread.sleep(fakeNetworkTimeCost);
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }

                        FakeToken fakeToken = new FakeToken();
                        fakeToken.token = createToken();
                        return fakeToken;
                    }
                });
    }

    private static String createToken() {
        return "fake_token_" + System.currentTimeMillis() % 10000;
    }

    public Observable<FakeThing> getFakeData(FakeToken fakeToken) {
        return Observable.just(fakeToken)
                .map(new Function<FakeToken, FakeThing>() {
                    @Override
                    public FakeThing apply(FakeToken fakeToken) {
                        // Add some random delay to mock the network delay
                        int fakeNetworkTimeCost = random.nextInt(500) + 500;
                        try {
                            Thread.sleep(fakeNetworkTimeCost);
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }

                        if (fakeToken.expired) {
                            throw new IllegalArgumentException("Token expired!");
                        }

                        FakeThing fakeData = new FakeThing();
                        fakeData.id = (int) (System.currentTimeMillis() % 1000);
                        fakeData.name = "FAKE_USER_" + fakeData.id;
                        return fakeData;
                    }
                });
    }
}

FakeToken .class

public class FakeToken {
    public String token;
    public boolean expired;

    public FakeToken() {
    }

    public FakeToken(boolean expired) {
        this.expired = expired;
    }
}

FakeThing .class

// (c)2016 Flipboard Inc, All Rights Reserved.

package com.rengwuxian.rxjavasamples.model;

public class FakeThing {
    public int id;
    public String name;
}

解释：getFakeToken方法利用map将string转换成FakeToken，最后返回的是携带了fakeToken.token的FakeToken对象；getFakeData也是类似

4.再看NetWork的封装：

// (c)2016 Flipboard Inc, All Rights Reserved.

package com.rengwuxian.rxjavasamples.network;

import com.rengwuxian.rxjavasamples.network.api.FakeApi;
import com.rengwuxian.rxjavasamples.network.api.GankApi;
import com.rengwuxian.rxjavasamples.network.api.ZhuangbiApi;

import okhttp3.OkHttpClient;
import retrofit2.CallAdapter;
import retrofit2.Converter;
import retrofit2.Retrofit;
import retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory;
import retrofit2.converter.gson.GsonConverterFactory;

public class Network {
    private static ZhuangbiApi zhuangbiApi;
    private static GankApi gankApi;
    private static FakeApi fakeApi;
    private static OkHttpClient okHttpClient = new OkHttpClient();
    private static Converter.Factory gsonConverterFactory = GsonConverterFactory.create();
    private static CallAdapter.Factory rxJavaCallAdapterFactory = RxJava2CallAdapterFactory.create();

    public static ZhuangbiApi getZhuangbiApi() {
        if (zhuangbiApi == null) {
            Retrofit retrofit = new Retrofit.Builder()
                    .client(okHttpClient)
                    .baseUrl("http://www.zhuangbi.info/")
                    .addConverterFactory(gsonConverterFactory)
                    .addCallAdapterFactory(rxJavaCallAdapterFactory)
                    .build();
            zhuangbiApi = retrofit.create(ZhuangbiApi.class);
        }
        return zhuangbiApi;
    }

    public static GankApi getGankApi() {
        if (gankApi == null) {
            Retrofit retrofit = new Retrofit.Builder()
                    .client(okHttpClient)
                    .baseUrl("http://gank.io/api/")
                    .addConverterFactory(gsonConverterFactory)
                    .addCallAdapterFactory(rxJavaCallAdapterFactory)
                    .build();
            gankApi = retrofit.create(GankApi.class);
        }
        return gankApi;
    }

    public static FakeApi getFakeApi() {
        if (fakeApi == null) {
            fakeApi = new FakeApi();
        }
        return fakeApi;
    }
}

解释：最开始那三个接口的获取
5.ZhuangbiApi 的使用

    private void search(String key) {
        Log.d("liwenpeng","key:"+key);
        disposable = Network.getZhuangbiApi()
                .search(key)
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Consumer<List<ZhuangbiImage>>() {
                    @Override
                    public void accept(@NonNull List<ZhuangbiImage> images) throws Exception {
                        swipeRefreshLayout.setRefreshing(false);
                        adapter.setImages(images);
                    }
                }, new Consumer<Throwable>() {
                    @Override
                    public void accept(@NonNull Throwable throwable) throws Exception {
                        swipeRefreshLayout.setRefreshing(false);
                        Toast.makeText(getActivity(), R.string.loading_failed, Toast.LENGTH_SHORT).show();
                    }
                });
    }

解释：IO线程进行search，结果到主线程处理

6.GankApi的使用：

    private void loadPage(int page) {
        swipeRefreshLayout.setRefreshing(true);
        unsubscribe();
        disposable = Network.getGankApi()
                .getBeauties(10, page)
                .map(GankBeautyResultToItemsMapper.getInstance())
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Consumer<List<Item>>() {
                    @Override
                    public void accept(@NonNull List<Item> items) throws Exception {
                        swipeRefreshLayout.setRefreshing(false);
                        pageTv.setText(getString(R.string.page_with_number, MapFragment.this.page));
                        adapter.setItems(items);
                    }
                }, new Consumer<Throwable>() {
                    @Override
                    public void accept(@NonNull Throwable throwable) throws Exception {
                        swipeRefreshLayout.setRefreshing(false);
                        Toast.makeText(getActivity(), R.string.loading_failed, Toast.LENGTH_SHORT).show();
                    }
                });
    }

看下map转换的function类：

// (c)2016 Flipboard Inc, All Rights Reserved.

package com.rengwuxian.rxjavasamples.util;

import com.rengwuxian.rxjavasamples.model.GankBeauty;
import com.rengwuxian.rxjavasamples.model.GankBeautyResult;
import com.rengwuxian.rxjavasamples.model.Item;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import io.reactivex.functions.Function;

public class GankBeautyResultToItemsMapper implements Function<GankBeautyResult, List<Item>> {
    private static GankBeautyResultToItemsMapper INSTANCE = new GankBeautyResultToItemsMapper();

    private GankBeautyResultToItemsMapper() {
    }

    public static GankBeautyResultToItemsMapper getInstance() {
        return INSTANCE;
    }

    @Override
    public List<Item> apply(GankBeautyResult gankBeautyResult) {
        List<GankBeauty> gankBeauties = gankBeautyResult.beauties;
        List<Item> items = new ArrayList<>(gankBeauties.size());
        SimpleDateFormat inputFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SS'Z'");
        SimpleDateFormat outputFormat = new SimpleDateFormat("yy/MM/dd HH:mm:ss");
        for (GankBeauty gankBeauty : gankBeauties) {
            Item item = new Item();
            try {
                Date date = inputFormat.parse(gankBeauty.createdAt);
                item.description = outputFormat.format(date);
            } catch (ParseException e) {
                e.printStackTrace();
                item.description = "unknown date";
            }
            item.imageUrl = gankBeauty.url;
            items.add(item);
        }
        return items;
    }
}

解释：此处使用了map将GankBeautyResult转换成List集合,这样在.subscribe的accept里得到的就是List了，再进行处理

7.ZhuangbiApi使用zip操作符

// (c)2016 Flipboard Inc, All Rights Reserved.

package com.rengwuxian.rxjavasamples.module.zip_3;

import android.graphics.Color;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import com.rengwuxian.rxjavasamples.BaseFragment;
import com.rengwuxian.rxjavasamples.network.Network;
import com.rengwuxian.rxjavasamples.R;
import com.rengwuxian.rxjavasamples.adapter.ItemListAdapter;
import com.rengwuxian.rxjavasamples.model.Item;
import com.rengwuxian.rxjavasamples.model.ZhuangbiImage;
import com.rengwuxian.rxjavasamples.util.GankBeautyResultToItemsMapper;

import java.util.ArrayList;
import java.util.List;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
import io.reactivex.Observable;
import io.reactivex.Observer;
import io.reactivex.android.schedulers.AndroidSchedulers;
import io.reactivex.annotations.NonNull;
import io.reactivex.functions.BiFunction;
import io.reactivex.functions.Consumer;
import io.reactivex.schedulers.Schedulers;

public class ZipFragment extends BaseFragment {
    @BindView(R.id.gridRv) RecyclerView gridRv;
    @BindView(R.id.swipeRefreshLayout) SwipeRefreshLayout swipeRefreshLayout;
    ItemListAdapter adapter = new ItemListAdapter();

    @OnClick(R.id.zipLoadBt)
    void load() {
        swipeRefreshLayout.setRefreshing(true);
        unsubscribe();
        disposable = Observable.zip(Network.getGankApi().getBeauties(200, 1).map(GankBeautyResultToItemsMapper.getInstance()),
                Network.getZhuangbiApi().search("装逼"),
                new BiFunction<List<Item>, List<ZhuangbiImage>, List<Item>>() {
                    @Override
                    public List<Item> apply(List<Item> gankItems, List<ZhuangbiImage> zhuangbiImages) {
                        List<Item> items = new ArrayList<Item>();
                        for (int i = 0; i < gankItems.size() / 2 && i < zhuangbiImages.size(); i++) {
                            items.add(gankItems.get(i * 2));
                            items.add(gankItems.get(i * 2 + 1));
                            Item zhuangbiItem = new Item();
                            ZhuangbiImage zhuangbiImage = zhuangbiImages.get(i);
                            zhuangbiItem.description = zhuangbiImage.description;
                            zhuangbiItem.imageUrl = zhuangbiImage.image_url;
                            items.add(zhuangbiItem);
                        }
                        return items;
                    }
                })
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Consumer<List<Item>>() {
                    @Override
                    public void accept(@NonNull List<Item> items) throws Exception {
                        swipeRefreshLayout.setRefreshing(false);
                        adapter.setItems(items);
                    }
                }, new Consumer<Throwable>() {
                    @Override
                    public void accept(@NonNull Throwable throwable) throws Exception {
                        swipeRefreshLayout.setRefreshing(false);
                        Toast.makeText(getActivity(), R.string.loading_failed, Toast.LENGTH_SHORT).show();
                    }
                });
    }

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_zip, container, false);
        ButterKnife.bind(this, view);

        gridRv.setLayoutManager(new GridLayoutManager(getActivity(), 2));
        gridRv.setAdapter(adapter);
        swipeRefreshLayout.setColorSchemeColors(Color.BLUE, Color.GREEN, Color.RED, Color.YELLOW);
        swipeRefreshLayout.setEnabled(false);
        return view;
    }


    @Override
    protected int getDialogRes() {
        return R.layout.dialog_zip;
    }

    @Override
    protected int getTitleRes() {
        return R.string.title_zip;
    }
}

解释：”Zip通过一个函数将多个Observable发送的事件结合到一起，然后发送这些组合到一起的事件. 它按照严格的顺序应用这个函数。它只发射与发射数据项最少的那个Observable一样多的数据。”，因此我们只需看 new BiFunction里的apply是如何处理的即可。这里是把List gankItems, List zhuangbiImages这两个list的数据用List保存返回。

8.FakeToken的处理flatMap

// (c)2016 Flipboard Inc, All Rights Reserved.

package com.rengwuxian.rxjavasamples.module.token_4;

import android.graphics.Color;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.widget.SwipeRefreshLayout;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import android.widget.Toast;

import com.rengwuxian.rxjavasamples.BaseFragment;
import com.rengwuxian.rxjavasamples.network.Network;
import com.rengwuxian.rxjavasamples.R;
import com.rengwuxian.rxjavasamples.network.api.FakeApi;
import com.rengwuxian.rxjavasamples.model.FakeThing;
import com.rengwuxian.rxjavasamples.model.FakeToken;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
import io.reactivex.Observable;
import io.reactivex.android.schedulers.AndroidSchedulers;
import io.reactivex.functions.Consumer;
import io.reactivex.functions.Function;
import io.reactivex.schedulers.Schedulers;

public class TokenFragment extends BaseFragment {

    @BindView(R.id.tokenTv) TextView tokenTv;
    @BindView(R.id.swipeRefreshLayout) SwipeRefreshLayout swipeRefreshLayout;

    @OnClick(R.id.requestBt)
    void upload() {
        swipeRefreshLayout.setRefreshing(true);
        unsubscribe();
        final FakeApi fakeApi = Network.getFakeApi();
        disposable = fakeApi.getFakeToken("fake_auth_code")
                .flatMap(new Function<FakeToken, Observable<FakeThing>>() {
                    @Override
                    public Observable<FakeThing> apply(FakeToken fakeToken) {
                        return fakeApi.getFakeData(fakeToken);
                    }
                })
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Consumer<FakeThing>() {
                    @Override
                    public void accept(FakeThing fakeData) {
                        swipeRefreshLayout.setRefreshing(false);
                        tokenTv.setText(getString(R.string.got_data, fakeData.id, fakeData.name));
                    }
                }, new Consumer<Throwable>() {
                    @Override
                    public void accept(Throwable throwable) {
                        swipeRefreshLayout.setRefreshing(false);
                        Toast.makeText(getActivity(), R.string.loading_failed, Toast.LENGTH_SHORT).show();
                    }
                });
    }

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_token, container, false);
        ButterKnife.bind(this, view);
        swipeRefreshLayout.setColorSchemeColors(Color.BLUE, Color.GREEN, Color.RED, Color.YELLOW);
        swipeRefreshLayout.setEnabled(false);
        return view;
    }

    @Override
    protected int getDialogRes() {
        return R.layout.dialog_token;
    }

    @Override
    protected int getTitleRes() {
        return R.string.title_token;
    }
}

解释：”FlatMap将一个发送事件的上游Observable变换为多个发送事件的Observables，然后将它们发射的事件合并后放进一个单独的Observable里.”

8.retrywhen

// (c)2016 Flipboard Inc, All Rights Reserved.

package com.rengwuxian.rxjavasamples.module.token_advanced_5;

import android.graphics.Color;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.widget.SwipeRefreshLayout;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import android.widget.Toast;

import com.rengwuxian.rxjavasamples.BaseFragment;
import com.rengwuxian.rxjavasamples.network.Network;
import com.rengwuxian.rxjavasamples.R;
import com.rengwuxian.rxjavasamples.network.api.FakeApi;
import com.rengwuxian.rxjavasamples.model.FakeThing;
import com.rengwuxian.rxjavasamples.model.FakeToken;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
import io.reactivex.Observable;
import io.reactivex.android.schedulers.AndroidSchedulers;
import io.reactivex.functions.Consumer;
import io.reactivex.functions.Function;
import io.reactivex.schedulers.Schedulers;

public class TokenAdvancedFragment extends BaseFragment {

    @BindView(R.id.tokenTv) TextView tokenTv;
    @BindView(R.id.swipeRefreshLayout) SwipeRefreshLayout swipeRefreshLayout;
    final FakeToken cachedFakeToken = new FakeToken(true);
    boolean tokenUpdated;

    @OnClick(R.id.invalidateTokenBt)
    void invalidateToken() {
        cachedFakeToken.expired = true;
        Toast.makeText(getActivity(), R.string.token_destroyed, Toast.LENGTH_SHORT).show();
    }

    @OnClick(R.id.requestBt)
    void upload() {
        tokenUpdated = false;
        swipeRefreshLayout.setRefreshing(true);
        unsubscribe();
        final FakeApi fakeApi = Network.getFakeApi();
        disposable = Observable.just(1)
                .flatMap(new Function<Object, Observable<FakeThing>>() {
                    @Override
                    public Observable<FakeThing> apply(Object o) {
                        return cachedFakeToken.token == null
                                ? Observable.<FakeThing>error(new NullPointerException("Token is null!"))
                                : fakeApi.getFakeData(cachedFakeToken);
                    }
                })
                .retryWhen(new Function<Observable<? extends Throwable>, Observable<?>>() {
                    @Override
                    public Observable<?> apply(Observable<? extends Throwable> observable) {
                        return observable.flatMap(new Function<Throwable, Observable<?>>() {
                            @Override
                            public Observable<?> apply(Throwable throwable) {
                                if (throwable instanceof IllegalArgumentException || throwable instanceof NullPointerException) {
                                    return fakeApi.getFakeToken("fake_auth_code")
                                            .doOnNext(new Consumer<FakeToken>() {
                                                @Override
                                                public void accept(FakeToken fakeToken) {
                                                    tokenUpdated = true;
                                                    cachedFakeToken.token = fakeToken.token;
                                                    cachedFakeToken.expired = fakeToken.expired;
                                                }
                                            });
                                }
                                return Observable.error(throwable);
                            }
                        });
                    }
                })
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Consumer<FakeThing>() {
                    @Override
                    public void accept(FakeThing fakeData) {
                        swipeRefreshLayout.setRefreshing(false);
                        String token = cachedFakeToken.token;
                        if (tokenUpdated) {
                            token += "(" + getString(R.string.updated) + ")";
                        }
                        tokenTv.setText(getString(R.string.got_token_and_data, token, fakeData.id, fakeData.name));
                    }
                }, new Consumer<Throwable>() {
                    @Override
                    public void accept(Throwable throwable) {
                        swipeRefreshLayout.setRefreshing(false);
                        Toast.makeText(getActivity(), R.string.loading_failed, Toast.LENGTH_SHORT).show();
                    }
                });
    }

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_token_advanced, container, false);
        ButterKnife.bind(this, view);
        swipeRefreshLayout.setColorSchemeColors(Color.BLUE, Color.GREEN, Color.RED, Color.YELLOW);
        swipeRefreshLayout.setEnabled(false);
        return view;
    }

    @Override
    protected int getDialogRes() {
        return R.layout.dialog_token_advanced;
    }

    @Override
    protected int getTitleRes() {
        return R.string.title_token_advanced;
    }
}

解释：注意retryWhen的用法