java - 如何在android retrofit中上传文件时显示进度条

Question

我正在使用改造开发一个 Android 应用程序。我想使用参数将任何类型的文件上传到我的服务器。例如在我的应用程序中有文本字段，如电子邮件和文件上传字段。当我输入字段并单击提交按钮时。它显示上传文件和发送文件和数据到服务器的百分比。当上传过程进行时，它想要显示已完成文件的百分比。怎么可能？ 有没有引用网站或教程？ 请帮帮我好吗？

Answer 1

创建这个界面

public interface ProgressListener {
                void transferred(long num);
            }

还有这个类

    public class CountingTypedFile extends TypedFile {

        private static final int BUFFER_SIZE = 4096;

        private final ProgressListener listener;

        public CountingTypedFile(String mimeType, File file, ProgressListener listener) {
            super(mimeType, file);
            this.listener = listener;
        }

        @Override
        public void writeTo(OutputStream out) throws IOException {

            byte[] buffer = new byte[BUFFER_SIZE];
            FileInputStream in = new FileInputStream(super.file());
            long total = 0;

            try {

                int read;
                while ((read = in.read(buffer)) != -1) {

                    total += read;
                    out.write(buffer, 0, read);

                    try{
                        if (this.listener != null)
                            this.listener.transferred(total);
                    }catch (Exception e){

                    }

                }
            } finally {
                in.close();
            }
        }
    }

定义这个方法

@POST("/{path}")
    public JsonObject makeRequestForAttachmentsUpload(@Path(value = "path", encode = false) String path, @Body MultipartTypedOutput multipartTypedOutput);

然后像这样调用上传方法

    RestClient restClient = new RestClient();
    ApiService apiService = restClient.getApiService();

MultipartTypedOutput multipartTypedOutput = new MultipartTypedOutput();
    // add and string parameters            
    for (String key : requestParams.keySet()) {
                    multipartTypedOutput.addPart(key, new TypedString(requestParams.get(key)));
                }

    // add attchments
                multipartTypedOutput.addPart(attachmentName, new CountingTypedFile(attachmentType, new File(attachmentPath), listener));
apiService.makeRequestForAttachmentsUpload(requestName, multipartTypedOutput);

并通过定义此监听器来监听进度

listener = new DPAPIService.ProgressListener() {
                @Override
                public void transferred(long num) {
                    publishProgress(((num / (float) fileSize)));
                }
        };