Question

我正在尝试实施一个进度条来指示多部分文件上传的进度。

我已经阅读了对这个答案的评论 - https://stackoverflow.com/a/24285633/1022454，我必须将接收器传递给RequestBody并提供跟踪移动字节的回调。

我创建了一个自定义RequestBody并使用CustomSink类包装了接收器，但是通过调试我可以看到字节是由RealBufferedSink ln 44写的，而自定义接收器写入方法只运行一次，而不是允许我跟踪移动的字节。

    private class CustomRequestBody extends RequestBody {

    MediaType contentType;
    byte[] content;

    private CustomRequestBody(final MediaType contentType, final byte[] content) {
        this.contentType = contentType;
        this.content = content;
    }

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

    @Override
    public long contentLength() {
        return content.length;
    }

    @Override
    public void writeTo(BufferedSink sink) throws IOException {
        CustomSink customSink = new CustomSink(sink);
        customSink.write(content);

    }
}


private class CustomSink implements BufferedSink {

    private static final String TAG = "CUSTOM_SINK";

    BufferedSink bufferedSink;

    private CustomSink(BufferedSink bufferedSink) {
        this.bufferedSink = bufferedSink;
    }

    @Override
    public void write(Buffer source, long byteCount) throws IOException {
        Log.d(TAG, "source size: " + source.size() + " bytecount" + byteCount);
        bufferedSink.write(source, byteCount);
    }

    @Override
    public void flush() throws IOException {
        bufferedSink.flush();
    }

    @Override
    public Timeout timeout() {
        return bufferedSink.timeout();
    }

    @Override
    public void close() throws IOException {
        bufferedSink.close();
    }

    @Override
    public Buffer buffer() {
        return bufferedSink.buffer();
    }

    @Override
    public BufferedSink write(ByteString byteString) throws IOException {
        return bufferedSink.write(byteString);
    }

    @Override
    public BufferedSink write(byte[] source) throws IOException {
        return bufferedSink.write(source);
    }

    @Override
    public BufferedSink write(byte[] source, int offset, int byteCount) throws IOException {
        return bufferedSink.write(source, offset, byteCount);
    }

    @Override
    public long writeAll(Source source) throws IOException {
        return bufferedSink.writeAll(source);
    }

    @Override
    public BufferedSink writeUtf8(String string) throws IOException {
        return bufferedSink.writeUtf8(string);
    }

    @Override
    public BufferedSink writeString(String string, Charset charset) throws IOException {
        return bufferedSink.writeString(string, charset);
    }

    @Override
    public BufferedSink writeByte(int b) throws IOException {
        return bufferedSink.writeByte(b);
    }

    @Override
    public BufferedSink writeShort(int s) throws IOException {
        return bufferedSink.writeShort(s);
    }

    @Override
    public BufferedSink writeShortLe(int s) throws IOException {
        return bufferedSink.writeShortLe(s);
    }

    @Override
    public BufferedSink writeInt(int i) throws IOException {
        return bufferedSink.writeInt(i);
    }

    @Override
    public BufferedSink writeIntLe(int i) throws IOException {
        return bufferedSink.writeIntLe(i);
    }

    @Override
    public BufferedSink writeLong(long v) throws IOException {
        return bufferedSink.writeLong(v);
    }

    @Override
    public BufferedSink writeLongLe(long v) throws IOException {
        return bufferedSink.writeLongLe(v);
    }

    @Override
    public BufferedSink emitCompleteSegments() throws IOException {
        return bufferedSink.emitCompleteSegments();
    }

    @Override
    public OutputStream outputStream() {
        return bufferedSink.outputStream();
    }
}

有没有人举例说明我会怎么做？

Answer 1

您必须创建一个自定义RequestBody并覆盖writeTo方法，然后您必须将您的文件分段发送到接收器。在每个段之后刷新接收器非常重要，否则您的进度条将快速填满，而文件实际上不会通过网络发送，因为内容将保留在接收器中（其作用类似于缓冲区）。

public class CountingFileRequestBody extends RequestBody {

    private static final int SEGMENT_SIZE = 2048; // okio.Segment.SIZE

    private final File file;
    private final ProgressListener listener;
    private final String contentType;

    public CountingFileRequestBody(File file, String contentType, ProgressListener listener) {
        this.file = file;
        this.contentType = contentType;
        this.listener = listener;
    }

    @Override
    public long contentLength() {
        return file.length();
    }

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

    @Override
    public void writeTo(BufferedSink sink) throws IOException {
        Source source = null;
        try {
            source = Okio.source(file);
            long total = 0;
            long read;

            while ((read = source.read(sink.buffer(), SEGMENT_SIZE)) != -1) {
                total += read;
                sink.flush();
                this.listener.transferred(total);

            }
        } finally {
            Util.closeQuietly(source);
        }
    }

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

}

您可以找到一个完整的实现，支持在AdapterView中显示进度，还可以在我的要点上取消上传：https://gist.github.com/eduardb/dd2dc530afd37108e1ac

Answer 2

我们只需要创建自定义RequestBody，无需实现自定义BufferedSink。我们可以分配Okio缓冲区来读取图像文件，并将此缓冲区连接到接收器。

有关示例，请参阅以下createCustomRequestBody功能

public static RequestBody createCustomRequestBody(final MediaType contentType, final File file) {
    return new RequestBody() {
        @Override public MediaType contentType() {
            return contentType;
        }
        @Override public long contentLength() {
            return file.length();
        }
        @Override public void writeTo(BufferedSink sink) throws IOException {
            Source source = null;
            try {
                source = Okio.source(file);
                //sink.writeAll(source);
                Buffer buf = new Buffer();
                Long remaining = contentLength();
                for (long readCount; (readCount = source.read(buf, 2048)) != -1; ) {
                    sink.write(buf, readCount);
                    Log.d(TAG, "source size: " + contentLength() + " remaining bytes: " + (remaining -= readCount));
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    };
}

使用 -

.addPart(
    Headers.of("Content-Disposition", "form-data; name=\"image\""),
    createCustomRequestBody(MediaType.parse("image/png"), new File("test.jpg")))
.build()

Answer 3

这件事很棒！

摇篮

dependencies {
  compile 'io.github.lizhangqu:coreprogress:1.0.2'
}

//wrap your original request body with progress
RequestBody requestBody = ProgressHelper.withProgress(body, new ProgressUIListener()....}

这里有完整的示例代码 https://github.com/lizhangqu/CoreProgress

使用OKHTTP跟踪多部分文件上载的进度

3 个答案: