Rxjava+Retrofit使用心得

一、Rxjava+Retrofit的包依赖

//RxJava
implementation "io.reactivex.rxjava2:rxjava:2.1.0" 
implementation "io.reactivex.rxjava2:rxandroid:2.0.1" 

//Retrofit
implementation 'com.squareup.retrofit2:retrofit:2.4.0'
implementation 'com.squareup.retrofit2:converter-gson:2.4.0'
implementation 'com.squareup.retrofit2:adapter-rxjava2:2.3.0'

二、Rxjava+Retrofit的使用

<!--相关权限-->
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

/**
 * 创建日期：2020/5/27 0027
 *
 * @author :Gentle Wen
 * describe:
 */
public class MainViewModel extends BaseViewModel {
    private final Retrofit retrofit;
    private String TAG = getClass().getSimpleName();

    public MainViewModel() {
        retrofit = new Retrofit.Builder()
                .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                .addConverterFactory(GsonConverterFactory.create())
                .baseUrl("http://xxx.xxx.xx/api")
                .build();
    }

    @SuppressLint("CheckResult")
    public void getApiService() {
        ApiService apiService = retrofit.create(ApiService.class);
        apiService.getApiResponse(new MainParams())
                .subscribeOn(Schedulers.io())
                .flatMap(new Function<MainResponse, ObservableSource<MainData>>() {
                    @Override
                    public ObservableSource<MainData> apply(MainResponse response){
                        Log.i(TAG, "apply: "+"加载到了Response："+response.toString());
                        return Observable.fromIterable(response.getDataInfo());
                    }
                })
                .flatMap(new Function<MainData, ObservableSource<String>>() {
                    @Override
                    public ObservableSource<String> apply(MainData mainData)  {
                        Log.i(TAG, "apply: "+"加载每个Data："+mainData.toString());
                        Log.i(TAG, "apply: "+"servicePic："+mainData.getServicePic());
                        String servicePic = mainData.getServicePic();
                        String[] urls = servicePic.split("#");
                        return Observable.fromIterable(Arrays.asList(urls));
                    }
                })
                .map(new Function<String, Bitmap>() {
                    @Override
                    public Bitmap apply(String s) throws Exception {
                        Log.i(TAG, "apply: "+"加载图片："+s);
                        URL url = new URL(s);
                        HttpURLConnection httpURLConnection
                            = (HttpURLConnection) url.openConnection();
                        httpURLConnection.setConnectTimeout(10 * 1000);
                        int responseCode = httpURLConnection.getResponseCode();
                        if (responseCode == HttpURLConnection.HTTP_OK) {
                            InputStream inputStream = httpURLConnection.getInputStream();
                            Bitmap bitmap = BitmapFactory.decodeStream(inputStream);
                            return bitmap;
                        }
                        return null;
                    }
                })
                .map(new Function<Bitmap, Bitmap>() {
                    @Override
                    public Bitmap apply(Bitmap bitmap) throws Exception {
                        String dirName = "Rxjava";
                        String imageName = System.currentTimeMillis()+".png";
                        String imageFilePath = Environment.getExternalStorageDirectory()
                        .getAbsolutePath()+"/"+dirName;
                        
                        File bitmapDir= new File(imageFilePath);
                        if (bitmapDir.exists()){
                            Log.i(TAG, "apply: "+bitmapDir.getPath()+"文件已存在");
                        }else {
                            bitmapDir.mkdir();
                            Log.i(TAG, "apply: "+"创建文件夹"+bitmapDir.getPath());
                        }
                        File imageFile = new File(bitmapDir.getPath()+"/"+imageName);
                        if (!imageFile.exists()){
                            imageFile.createNewFile();
                        }

                        FileOutputStream fileOutputStream
                            = new FileOutputStream(imageFile);
                            
                        try {
                            bitmap.compress(
                            Bitmap.CompressFormat.PNG
                            , 100
                            ,fileOutputStream);
                            
                            Log.i(TAG, "apply: 保存成功："+imageFile.getPath());
                        } catch (Exception e) {
                            e.printStackTrace();
                            Log.i(TAG, "apply: 保存失败");
                        }finally {
                            fileOutputStream.flush();
                            fileOutputStream.close();
                        }
                        return bitmap;
                    }
                })
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Observer<Bitmap>() {
                    @Override
                    public void onSubscribe(Disposable d) {
                        Log.i(TAG, "onSubscribe: ");
                    }

                    @Override
                    public void onNext(Bitmap bitmap) {
                        Log.i(TAG, "onNext: " + bitmap);
                    }

                    @Override
                    public void onError(Throwable e) {
                        Log.i(TAG, "onError: "+e.getMessage());
                    }

                    @Override
                    public void onComplete() {
                        Log.i(TAG, "onComplete: ");
                    }
                });
    }
}

三、结果显示

I/MainViewModel: onSubscribe: 
I/MainViewModel: apply: 加载到了Response：PublicResponse 
I/MainViewModel: apply: 加载每个Data：MainData
I/MainViewModel: apply: servicePic：http://xxx.xxx.xx/upload/1548062920491shi887jian.jpg
I/MainViewModel: apply: 加载图片：http://xxx.xxx.xx/upload/1548062920491shi887jian.jpg
I/MainViewModel: apply: /storage/sdcard0/Rxjava文件已存在
I/MainViewModel: apply: 保存成功：/storage/sdcard0/Rxjava/1590566231417.png
I/MainViewModel: apply: 加载每个Data：MainData
I/MainViewModel: onNext: android.graphics.Bitmap@30770e1c
I/MainViewModel: apply: servicePic：http://xxx.xxx.xx/upload/1585015823125shi58jian.jpg
I/MainViewModel: apply: 加载图片：http://xxx.xxx.xx/upload/1585015823125shi58jian.jpg
I/MainViewModel: apply: /storage/sdcard0/Rxjava文件已存在
I/MainViewModel: apply: 保存成功：/storage/sdcard0/Rxjava/1590566231787.png
I/MainViewModel: onNext: android.graphics.Bitmap@2ea5ba25
/MainViewModel: onComplete: 

四、总结

​ Rxjava强大的框架令人叹为观止，但是Rxjava最强大的地方并不是如何去使用，而是他的Rx思想，从而衍生出各种Rx相关的框架比如（RxView..），配合Retrofit使用这个是真的香啊。