Android RXJava+Retrofit初体验新闻APP

偏执的太偏执、 2021-09-30 00:44 351阅读 0赞

一个RXJava+Retrofit的简单应用。接口调用天行数据。这里还使用了一些开源库。glide加载图片，Easyrecyclerview一个封装的recyclerview。  
[项目地址][Link 1][https://github.com/icecrea/helloretrofit][Link 1]  
添加的依赖如下。

compile 'com.android.support:recyclerview-v7:24.2.0'
    
    compile 'com.jude:easyrecyclerview:4.4.0'
    
    compile 'com.android.support:design:24.2.1'
    
    compile 'com.squareup.retrofit2:retrofit-converters:2.1.0'
    
    compile 'com.squareup.retrofit2:converter-gson:2.1.0'
    
    compile 'io.reactivex:rxandroid:1.2.1'
    
    compile 'com.squareup.retrofit2:adapter-rxjava:2.1.0'
    
    compile 'com.squareup.retrofit2:retrofit:2.1.0'
    
    compile 'com.squareup.retrofit2:converter-scalars:2.1.0'
    
    compile 'com.github.bumptech.glide:glide:3.7.0'

根据retrofit的特性 首先声明一个接口 （配合RXjava主要用到第一个。第二个是在仅retrofit的时候用的）

public interfaceApiService {
    
    @GET("apple/")
    
    ObservablegetNewsData(@Query("key")String key,@Query("num") String num,@Query("page")intpage);
    
    @GET("apple/")
    
    CallgetNewsDataCall(@Query("key")String key,@Query("num") String num,@Query("page")intpage);
    
    }

发送网络请求获取数据的代码如下

public voidgetData(){
    
    Log.d("page",page+"");
    
    Retrofit retrofit =newRetrofit.Builder()
    
    .baseUrl("http://api.tianapi.com/")
    
    //增加返回值为String的支持
    
    .addConverterFactory(ScalarsConverterFactory.create())
    
    //增加返回值为Gson的支持(以实体类返回)
    
    .addConverterFactory(GsonConverterFactory.create())
    
    //增加返回值为Oservable的支持
    
    .addCallAdapterFactory(RxJavaCallAdapterFactory.create())
    
    .build();
    
    ApiService service=retrofit.create(ApiService.class);
    
    //用rxjava+retroift进行网络请求
    
    service.getNewsData("6ccd95e92c8481e4b1584316244b6a97","10",page)
    
    .subscribeOn(Schedulers.io())
    
    .map(newFunc1>() {
    
    @Override
    
    publicListcall(NewsGson newsGson) {
    
    returnnewsGson.getNewslist();
    
    }
    })
    
    .observeOn(AndroidSchedulers.mainThread())
    
    .subscribe(newSubscriber>() {
    
    @Override
    
    public voidonCompleted() {
    
    }
    
    @Override
    
    public voidonError(Throwable e) {
    
    Toast.makeText(MainActivity.this,
    
    "网络连接失败",Toast.LENGTH_LONG).show();
    
    }
    
    @Override
    
    public voidonNext(List newsList) {
    
    //几个小时的教训！此处不能这样等于
    
    //  newsListx=newsList;
    
    //这个可以
    
    //newsListx.addAll(newsList);
    
    adapter.addAll(newsList);
    
    }
    
    });
    
    page=page+1;
    
    }

根据返回数据的格式建立对应的实体类NewsGson和News  
因为Retrofit通过配合RXjava可以直接将数据转换成JSON格式（即实体类非常方便操作）

//这两种是进行GSON格式转换和字符串转换的依赖
        compile 'com.squareup.retrofit2:converter-gson:2.1.0'
        compile 'com.squareup.retrofit2:converter-scalars:2.1.0'

public class NewsGson {
        /**
         * code : 200
         * msg : success
         * newslist : [{"ctime":"2017-03-03 11:07","title":"台湾通缉犯遭警方盘查谎报身份 母亲：你别演了","description":"搜狐社会","picUrl":"","url":"http://news.sohu.com/20170303/n482240919.shtml"},{"ctime":"2017-03-03 11:16","title":"环卫工怕82岁老人孤单 带着患脑梗婆婆扫大街","description":"搜狐社会","picUrl":"","url":"http://news.sohu.com/20170303/n482247355.shtml"},{"ctime":"2017-03-03 11:16","title":"女子为美容一年花80多万 借完亲友又借高利贷","description":"搜狐社会","picUrl":"","url":"http://news.sohu.com/20170303/n482247354.shtml"},{"ctime":"2017-03-03 11:17","title":"市民拎大桶直饮水点排队取水 记者拍照被骂","description":"搜狐社会","picUrl":"","url":"http://news.sohu.com/20170303/n482247357.shtml"},{"ctime":"2017-03-03 11:19","title":"天坛公园回应厕纸被\u201c打包\u201d：不会取消免费厕纸","description":"搜狐社会","picUrl":"","url":"http://news.sohu.com/20170303/n482242422.shtml"},{"ctime":"2017-03-03 11:22","title":"陕西一路段10公里设3个收费站 管理方：可以撤俩","description":"搜狐社会","picUrl":"http://photocdn.sohu.com/20170303/Img482247363_ss.jpg","url":"http://news.sohu.com/20170303/n482243280.shtml"},{"ctime":"2017-03-03 11:28","title":"广西土豪村探秘：身家亿元以上2人 千万级14人","description":"搜狐社会","picUrl":"http://photocdn.sohu.com/20170303/Img482240921_ss.jpg","url":"http://news.sohu.com/20170303/n482245153.shtml"},{"ctime":"2017-03-03 11:29","title":"楼盘烂尾10年：业主等房结婚 未婚妻等成别人妻","description":"搜狐社会","picUrl":"http://photocdn.sohu.com/20170303/Img482243281_ss.jpeg","url":"http://news.sohu.com/20170303/n482245324.shtml"},{"ctime":"2017-03-03 11:32","title":"49岁古装女神张敏宣布复出 往日剧照现盛世美颜","description":"搜狐社会","picUrl":"http://photocdn.sohu.com/20170303/Img482245154_ss.jpeg","url":"http://news.sohu.com/20170303/n482247499.shtml"},{"ctime":"2017-03-03 11:33","title":"90后相亲大会：2个小时里大家都在玩手机","description":"搜狐社会","picUrl":"http://photocdn.sohu.com/20170303/Img482245325_ss.jpeg","url":"http://news.sohu.com/20170303/n482247179.shtml"}]
         */
    
        private int code;
        private String msg;
        private List<News> newslist;
    
        public int getCode() {
            return code;
        }
    
        public void setCode(int code) {
            this.code = code;
        }
    
        public String getMsg() {
            return msg;
        }
    
        public void setMsg(String msg) {
            this.msg = msg;
        }
    
        public List<News> getNewslist() {
            return newslist;
        }
    
        public void setNewslist(List<News> newslist) {
            this.newslist = newslist;
        }
    
    
    }

public class News {
        /**
         * ctime : 2017-03-03 11:07
         * title : 台湾通缉犯遭警方盘查谎报身份 母亲：你别演了
         * description : 搜狐社会
         * picUrl :
         * url : http://news.sohu.com/20170303/n482240919.shtml
         */
    
        private String ctime;
        private String title;
        private String description;
        private String picUrl;
        private String url;
    
        public String getCtime() {
            return ctime;
        }
    
        public void setCtime(String ctime) {
            this.ctime = ctime;
        }
    
        public String getTitle() {
            return title;
        }
    
        public void setTitle(String title) {
            this.title = title;
        }
    
        public String getDescription() {
            return description;
        }
    
        public void setDescription(String description) {
            this.description = description;
        }
    
        public String getPicUrl() {
            return picUrl;
        }
    
        public void setPicUrl(String picUrl) {
            this.picUrl = picUrl;
        }
    
        public String getUrl() {
            return url;
        }
    
        public void setUrl(String url) {
            this.url = url;
        }
    }

接下来是搭建适配器 因为用到了EasyRecyclerView 所以方法和recyclerview有些不同 (该控件地址：[https://github.com/Jude95/EasyRecyclerView][https_github.com_Jude95_EasyRecyclerView])  
同时还用Glide对图片进行平滑加载

布局文件的配置

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:orientation="vertical"
        tools:context="com.example.helloretroift.MainActivity">
        <android.support.design.widget.CoordinatorLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent">
        <android.support.design.widget.AppBarLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
            app:layout_scrollFlags="scroll|enterAlways|snap"
            ></android.support.v7.widget.Toolbar>
        </android.support.design.widget.AppBarLayout>
        <com.jude.easyrecyclerview.EasyRecyclerView
            android:id="@+id/recycler_view"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior"
            app:recyclerPadding="8dp"
            app:recyclerClipToPadding="true"
            app:scrollbarStyle="insideOverlay"
            app:scrollbars="none"
            />
        </android.support.design.widget.CoordinatorLayout>
    </LinearLayout>

NewsViewHolder继承了BaseViewHolder. 这个ViewHolder将每个item与adapter解耦。adapter只管实例化对应ViewHolder.每个Item的view生成,findviewbyid,UI修改都由viewHolder自己管理。

public class NewsViewHolder extends BaseViewHolder<News> {
        private TextView title;
        private ImageView imageView;
        private TextView date;
    
        @Override
        public void setData(News news) {
            date.setText(news.getCtime());
            title.setText(news.getTitle());
            Glide.with(MyApplication.getContext()).load(news.getPicUrl()).into(imageView);
        }
    
        public NewsViewHolder(ViewGroup parent) {
            super(parent, R.layout.news_recycler_item);
            title=$(R.id.news_item_title);
            date=$(R.id.news_item_date);
            imageView=$(R.id.news_item_image);
        }
    }

NewsAdapter中继承了RecyclerArrayAdapter<T> ,这个Adapter与本RecyclerView没有任何耦合。你可以使用其他adapter。也可以把本adapter用于其他RecyclerView

public class NewsAdapter extends RecyclerArrayAdapter<News> {
    
        public NewsAdapter(Context context){
            super(context);
        }
    
        @Override
        public BaseViewHolder OnCreateViewHolder(ViewGroup parent, int viewType) {
            return new NewsViewHolder(parent);
        }
    
    }

在activity中添加下拉刷新，上拉更多，点击事件

recyclerView.setRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
                @Override
                public void onRefresh() {
                    adapter.clear();
                    page=0;
                    getData();
                }
            });
            adapter.setMore(R.layout.view_more, new RecyclerArrayAdapter.OnMoreListener() {
                @Override
                public void onMoreShow() {
                    getData();
                }
    
                @Override
                public void onMoreClick() {
    
                }
            });
            adapter.setOnItemClickListener(new RecyclerArrayAdapter.OnItemClickListener() {
                @Override
                public void onItemClick(int position) {
                    ArrayList<String> data=new ArrayList<String>();
                    data.add(adapter.getAllData().get(position).getPicUrl());
                    data.add(adapter.getAllData().get(position).getUrl());
                    Intent intent=new Intent(MainActivity.this,NewsDetailsActivity.class);
                    Bundle bundle=new Bundle();
                    bundle.putStringArrayList("data",data);
                    intent.putExtras(bundle);
                    startActivity(intent);
                }
            });

这样就完成了初始界面

![5057999-c027fe7a5e8c1de4.jpg][]

S70307-100940.jpg

接下来通过WEBVIEW设置点击之后的详情界面 具有可伸缩下拉框，透明导航栏等效果

<?xml version="1.0" encoding="utf-8"?>
    <android.support.design.widget.CoordinatorLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fitsSystemWindows="true">
    
        <android.support.design.widget.AppBarLayout
            android:layout_width="match_parent"
            android:layout_height="256dp"
            android:fitsSystemWindows="true"
            android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
            <android.support.design.widget.CollapsingToolbarLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:fitsSystemWindows="true"
                app:contentScrim="@color/colorPrimary"
                app:layout_scrollFlags="scroll|exitUntilCollapsed">
                <ImageView
                    android:src="@mipmap/ic_launcher"
                    android:id="@+id/ivImage"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:fitsSystemWindows="true"
                    android:scaleType="centerCrop"
                    app:layout_collapseMode="parallax"/>
                <android.support.v7.widget.Toolbar
                    android:id="@+id/toolbar"
                    android:layout_width="match_parent"
                    android:layout_height="?attr/actionBarSize"
                    app:layout_collapseMode="pin"></android.support.v7.widget.Toolbar>
            </android.support.design.widget.CollapsingToolbarLayout>
        </android.support.design.widget.AppBarLayout>
        <android.support.v4.widget.NestedScrollView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_behavior="@string/appbar_scrolling_view_behavior">
            <WebView
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:id="@+id/webview"></WebView>
        </android.support.v4.widget.NestedScrollView>
    </android.support.design.widget.CoordinatorLayout>

新闻详情的activity页面

public class NewsDetailsActivity extends AppCompatActivity {
        private Toolbar toolbar;
        private WebView webView;
        private ImageView imageView;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.news_detail);
            webView=(WebView)findViewById(R.id.webview);
            toolbar=(Toolbar)findViewById(R.id.toolbar);
            imageView=(ImageView)findViewById(R.id.ivImage);
            toolbar.setTitle("新闻详情");
            setSupportActionBar(toolbar);
            getSupportActionBar().setDisplayHomeAsUpEnabled(true);
            //新页面接受数据
            Bundle bundle=this.getIntent().getExtras();
            final ArrayList<String> data=bundle.getStringArrayList("data");
            Log.d("url",data.get(0));
            webView.getSettings().setJavaScriptEnabled(true);
            webView.setWebViewClient(new WebViewClient(){
            });
            webView.loadUrl(data.get(1));
            Glide.with(this).load(data.get(0)).error(R.mipmap.ic_launcher)
                    .fitCenter().into(imageView);
        }
    
        @Override
        public boolean onOptionsItemSelected(MenuItem item) {
            switch (item.getItemId()){
                case android.R.id.home:
                    finish();
                    return true;
            }
            return super.onOptionsItemSelected(item);
        }
    }

![5057999-7912aa25f88af56d.jpg][]

S70307-100947.jpg

上拉伸缩效果

![5057999-41f4e6e39b4a3527.jpg][]

S70307-100954.jpg

这样一个简单的结合RXJAVA和Retrofit的小应用就初步完成了！

--------------------

3月9日更新  
因为使用到了RXJAVA，而RXJAVA一个特性就是解耦性强。所以希望在原工程的基础上进行修改。做出一个集合多种标签查询的新闻APP。完成图如下。

![5057999-ecff100bf60e06a0.jpg][]

QQ图片20170309162231.jpg

首先是自定义接口的更新，利用了@PATH和@QUERY注释，在实际代码中只需要改动一行即可完成不同接口的查询工作，十分高效。

public interface ApiService {
        @GET("{part}/")
        Observable<NewsGson> getNewsData(@Path("part") String part, @Query("key") String key, @Query("num") String num, @Query("page") int page);
    }

然后主题采用了viewpager+fragment+tablayout  
fragment处代码.注意到：只需要设定数组，在不同fragment加载时传入不同的参数即可以进行不同查询。另外注意查询page是从1开始计数的。传入0会重复。

public class PageFragment extends Fragment {
        public static final String PATH = "args_page";
        private int mPage;
        private List<News> newsListx;
        private NewsAdapter adapter;
        private int page=1;
        private String part;
        private static String[] path={"social","guonei","world","huabian","tiyu","nba","football"
        ,"keji","startup","apple"};
    
        public static PageFragment newInstance(int position) {
            Bundle args = new Bundle();
    
            args.putString(PATH, path[position]);
            PageFragment fragment = new PageFragment();
            fragment.setArguments(args);
            return fragment;
        }
    
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            part = getArguments().getString(PATH);
            adapter=new NewsAdapter(getActivity());
            newsListx=new ArrayList<News>();
        }
    
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
            View view = inflater.inflate(R.layout.news_recycler,container,false);
            EasyRecyclerView recyclerView=(EasyRecyclerView)view.findViewById(R.id.recycler_view);
            LinearLayoutManager linearLayoutManager=new LinearLayoutManager(getActivity());
            recyclerView.setAdapter(adapter);
            recyclerView.setLayoutManager(linearLayoutManager);
    
            getData(part);
            SpaceDecoration itemDecoration = new SpaceDecoration((int) PixUtil.convertDpToPixel(8,getActivity()));//参数是距离宽度
            itemDecoration.setPaddingEdgeSide(true);//是否为左右2边添加padding.默认true.
            itemDecoration.setPaddingStart(true);//是否在给第一行的item添加上padding(不包含header).默认true.
            itemDecoration.setPaddingHeaderFooter(false);//是否对Header于Footer有效,默认false.
            recyclerView.addItemDecoration(itemDecoration);
            recyclerView.setRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
                @Override
                public void onRefresh() {
                    adapter.clear();
                    page=1;
                    getData(part);
                }
            });
            adapter.setMore(R.layout.view_more, new RecyclerArrayAdapter.OnMoreListener() {
                @Override
                public void onMoreShow() {
                    getData(part);
                }
    
                @Override
                public void onMoreClick() {
    
                }
            });
            adapter.setOnItemClickListener(new RecyclerArrayAdapter.OnItemClickListener() {
                @Override
                public void onItemClick(int position) {
                    ArrayList<String> data=new ArrayList<String>();
                    data.add(adapter.getAllData().get(position).getPicUrl());
                    data.add(adapter.getAllData().get(position).getUrl());
                    Intent intent=new Intent(getActivity(),NewsDetailsActivity.class);
                    Bundle bundle=new Bundle();
                    bundle.putStringArrayList("data",data);
                    intent.putExtras(bundle);
                    startActivity(intent);
                }
            });
            return view;
        }
    
        public void getData(String part){
            Log.d("page",page+"");
            Retrofit retrofit = new Retrofit.Builder()
                    .baseUrl("http://api.tianapi.com/")
                    //增加返回值为String的支持
                    .addConverterFactory(ScalarsConverterFactory.create())
                    //增加返回值为Gson的支持(以实体类返回)
                    .addConverterFactory(GsonConverterFactory.create())
                    //增加返回值为Oservable<T>的支持
                    .addCallAdapterFactory(RxJavaCallAdapterFactory.create())
                    .build();
            ApiService service=retrofit.create(ApiService.class);
            //用rxjava+retroift进行网络请求
            service.getNewsData(part,"6ccd95e92c8481e4b1584316244b6a97", "10", page)
                    .subscribeOn(Schedulers.io())
                    .map(new Func1<NewsGson, List<News>>() {
                        @Override
                        public List<News> call(NewsGson newsGson) {
                            return newsGson.getNewslist();
                        }
                    })
                    .observeOn(AndroidSchedulers.mainThread())
                    .subscribe(new Subscriber<List<News>>() {
                        @Override
                        public void onCompleted() {
                        }
    
                        @Override
                        public void onError(Throwable e) {
                            Log.d("hello",e.getMessage());
                            Toast.makeText(getActivity(),
                                    "网络连接失败", Toast.LENGTH_LONG).show();
                        }
    
                        @Override
                        public void onNext(List<News> newsList) {
                            //几个小时的教训！此处不能这样等于
                            //  newsListx=newsList;
                            //这个可以
                            //newsListx.addAll(newsList);
                            adapter.addAll(newsList);
                        }
                    });
            page=page+1;
        }
    }

FragmentAdapter设置。设置tablayout的标题.在activity中通过 **tabLayout.setupWithViewPager(viewPager);**进行绑定

public class MyFragmentAdapter extends FragmentPagerAdapter {
        public final int COUNT=10;
        private String[] titles=new String[]{"社会","国内","国际","娱乐","体育","NBA","足球","科技","创业","苹果"};
    
        public MyFragmentAdapter(FragmentManager fm) {
            super(fm);
        }
    
        @Override
        public Fragment getItem(int position) {
            return PageFragment.newInstance(position + 1);
        }
    
        @Override
        public int getCount() {
            return COUNT;
        }
    
        @Override
        public CharSequence getPageTitle(int position) {
            return titles[position];
        }
    }

这样一个分页多查询的新闻APP就完成了~

[Link 1]: https://link.jianshu.com?t=https://github.com/icecrea/helloretrofit
[https_github.com_Jude95_EasyRecyclerView]: https://link.jianshu.com?t=https://github.com/Jude95/EasyRecyclerView
[5057999-c027fe7a5e8c1de4.jpg]: /images/20210811/b94a5cae1e49406b8b942666fd980960.png
[5057999-7912aa25f88af56d.jpg]: /images/20210811/a33f1d964ad44f70a59494f3c999dfba.png
[5057999-41f4e6e39b4a3527.jpg]: /images/20210811/b6b524e3f61d4f9bb349aa16ba2cb947.png
[5057999-ecff100bf60e06a0.jpg]: /images/20210811/6878f264bc2f486084e1a3590431e6f9.png