ProgressCallback typedef Null safety

void ProgressCallback(
  1. int count,
  2. int total

Callback to listen the progress for sending/receiving data.

count is the length of the bytes have been sent/received.

total is the content length of the response/request body. 1.When receiving data: total is the request body length. 2.When receiving data: total will be -1 if the size of the response body is not known in advance, for example: response data is compressed with gzip or no content-length header.


typedef ProgressCallback = void Function(int count, int total);