Android Retrofit 2 JSON对象上传进度百分比

Question

我正在使用 Retrofit 2 将 JSON 上传到服务器。 JSON 有一些 BASE64 编码的图像，因此上传整个图像需要时间。我想查看上传的百分比。我已经找到了现有文件的解决方案，但这不是文件，服务器只接受这种形式。

Answer 1

对于有同样问题的其他人，我已经从这个库中改编了一个辅助类（ProgressOutputStream）：https://github.com/lizhangqu/CoreProgress，我的工作代码如下：（用于上传文件和上传 json）

import java.io.IOException;

import okhttp3.MediaType;
import okhttp3.RequestBody;
import okio.BufferedSink;
import okio.Okio;

public class UploadProgressRequestBody extends RequestBody {
    private final RequestBody requestBody;
    private final ProgressListener progressListener;

    public UploadProgressRequestBody(RequestBody requestBody) {
        this.requestBody = requestBody;
        this.progressListener = getDefaultProgressListener();
    }

    @Override public MediaType contentType() {
        return requestBody.contentType();
    }

    @Override public long contentLength() {
        try {
            return requestBody.contentLength();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return -1;
    }

    @Override
    public void writeTo(BufferedSink sink) throws IOException {
        if (progressListener == null) {
            requestBody.writeTo(sink);
            return;
        }
        ProgressOutputStream progressOutputStream = new ProgressOutputStream(sink.outputStream(), progressListener, contentLength());
        BufferedSink progressSink = Okio.buffer(Okio.sink(progressOutputStream));
        requestBody.writeTo(progressSink);
        progressSink.flush();
    }

    interface ProgressListener {
        void update(long bytesWritten, long contentLength);
    }

    private ProgressListener getDefaultProgressListener(){
        ProgressListener progressListener = new UploadProgressRequestBody.ProgressListener() {
            @Override public void update(long bytesRead, long contentLength) {
                System.out.println("bytesRead: "+bytesRead);
                System.out.println("contentLength: "+contentLength);
                System.out.format("%d%% done\n", (100 * bytesRead) / contentLength);
            }
        };

        return progressListener;
    }

}

============

import java.io.IOException;
import java.io.OutputStream;

class ProgressOutputStream extends OutputStream {
    private final OutputStream stream;
    private final UploadProgressRequestBody.ProgressListener listener;

    private long total;
    private long totalWritten;

    ProgressOutputStream(OutputStream stream, UploadProgressRequestBody.ProgressListener listener, long total) {
        this.stream = stream;
        this.listener = listener;
        this.total = total;
    }

    @Override
    public void write(byte[] b, int off, int len) throws IOException {
        this.stream.write(b, off, len);
        if (this.total < 0) {
            this.listener.update(-1, -1);
            return;
        }
        if (len < b.length) {
            this.totalWritten += len;
        } else {
            this.totalWritten += b.length;
        }
        this.listener.update(this.totalWritten, this.total);
    }

    @Override
    public void write(int b) throws IOException {
        this.stream.write(b);
        if (this.total < 0) {
            this.listener.update(-1, -1);
            return;
        }
        this.totalWritten++;
        this.listener.update(this.totalWritten, this.total);
    }

    @Override
    public void close() throws IOException {
        if (this.stream != null) {
            this.stream.close();
        }
    }

    @Override
    public void flush() throws IOException {
        if (this.stream != null) {
            this.stream.flush();
        }
    }
}

===========

    OkHttpClient client = new OkHttpClient.Builder()
    .addNetworkInterceptor(new Interceptor() {
        @Override public Response intercept(Chain chain) throws IOException {
            Request originalRequest = chain.request();

            if (originalRequest.body() == null) {
                return chain.proceed(originalRequest);
            }

            Request progressRequest = originalRequest.newBuilder()
                    .method(originalRequest.method(),
                            new UploadProgressRequestBody(originalRequest.body()))
                    .build();

            return chain.proceed(progressRequest);
        }
    }).build();

Retrofit retrofit = new Retrofit.Builder()
        .baseUrl(baseUrl)
        .client(client)
        .addConverterFactory(GsonConverterFactory.create())
        .build();