在Android中实现分块上传并显示进度的解决方法如下：

首先，确保你已经添加了对OkHttp和Retrofit库的依赖。

1. 创建一个接口定义上传文件的API：

public interface FileUploadService {
    @Multipart
    @POST("upload")
    Call uploadFile(
        @Part("description") RequestBody description,
        @Part MultipartBody.Part file
    );
}

2. 在Activity或Fragment中创建一个方法来执行上传操作：

private void uploadFile(File file) {
    // 创建RequestBody对象
    RequestBody requestBody = RequestBody.create(MediaType.parse("multipart/form-data"), file);

    // 创建MultipartBody.Part对象，用于封装文件数据
    MultipartBody.Part filePart = MultipartBody.Part.createFormData("file", file.getName(), requestBody);

    // 创建RequestBody对象，封装描述字符串
    RequestBody descPart = RequestBody.create(MediaType.parse("multipart/form-data"), "File description");

    // 创建retrofit实例
    Retrofit retrofit = new Retrofit.Builder()
        .baseUrl(BASE_URL)
        .client(new OkHttpClient.Builder().build())
        .addConverterFactory(GsonConverterFactory.create())
        .build();

    // 创建API接口实例
    FileUploadService service = retrofit.create(FileUploadService.class);

    // 创建Call对象，传入接口方法和参数
    Call call = service.uploadFile(descPart, filePart);

    // 执行异步上传操作
    call.enqueue(new Callback() {
        @Override
        public void onResponse(Call call, Response response) {
            // 上传成功处理逻辑
        }

        @Override
        public void onFailure(Call call, Throwable t) {
            // 上传失败处理逻辑
        }
    });
}

3. 如果你想显示上传进度，可以使用OkHttp的Interceptor来实现。创建一个ProgressRequestBody类来扩展RequestBody：

public class ProgressRequestBody extends RequestBody {
    private final RequestBody requestBody;
    private final ProgressListener listener;

    public ProgressRequestBody(RequestBody requestBody, ProgressListener listener) {
        this.requestBody = requestBody;
        this.listener = listener;
    }

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

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

    @Override
    public void writeTo(BufferedSink sink) throws IOException {
        BufferedSink bufferedSink;
        if (sink instanceof Buffer) {
            bufferedSink = Okio.buffer(sink);
        } else {
            bufferedSink = Okio.buffer(new ForwardingSink(sink) {
                long bytesWritten = 0L;
                long contentLength = 0L;

                @Override
                public void write(Buffer source, long byteCount) throws IOException {
                    super.write(source, byteCount);
                    if (contentLength == 0) {
                        contentLength = contentLength();
                    }
                    bytesWritten += byteCount;
                    listener.onProgress(bytesWritten, contentLength);
                }
            });
        }
        requestBody.writeTo(bufferedSink);
        bufferedSink.flush();
    }

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

4. 修改uploadFile方法，使用ProgressRequestBody来包装RequestBody：

private void uploadFile(File file) {
    // 创建RequestBody对象
    RequestBody requestBody = RequestBody.create(MediaType.parse("multipart/form-data"), file);

    // 创建ProgressRequestBody对象，用于监听上传进度
    ProgressRequestBody progressRequestBody = new ProgressRequestBody(requestBody, new ProgressRequestBody.ProgressListener() {
        @Override
        public void onProgress(long bytesWritten, long contentLength) {
            // 更新上传进度
            int progress = (int) (100 * bytesWritten / contentLength);
            // 更新UI进度条
            updateProgressBar(progress);
        }
    });

    // 创建MultipartBody.Part对象，用于封装文件数据
    MultipartBody.Part filePart = MultipartBody.Part.createFormData("file", file.getName(), progressRequestBody);

    // ...其它代码不变...
}

5. 最后，你可以在updateProgressBar方法中根据上传进度更新UI进度条：

private void updateProgressBar(int progress) {
    // 更新UI进度条
    progressBar.setProgress(progress);
}

以上是一个使用OkHttp和Retrofit库实现Android分块上传并显示