How to get Upload time remaining from Asynchronous Request? - iphone

Question

I m trying to upload an Image from iPhone to Server. I m Able to Do so But i need to show an Indicator.My code is
NSData *imageData = UIImageJPEGRepresentation(newImage, 90);
// setting up the URL to post to
NSString *urlString = [NSString stringWithFormat:#"URL",[[formater stringFromDate:now] stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
// setting up the request object now
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init] ;
[request setURL:[NSURL URLWithString:urlString]];
[request setHTTPMethod:#"POST"];
NSString *boundary = [NSString stringWithFormat:#"---------------------------14737809831466499882746641449"];
NSString *contentType = [NSString stringWithFormat:#"multipart/form-data; boundary=%#",boundary];
[request addValue:contentType forHTTPHeaderField: #"Content-Type"];
NSMutableData *body = [NSMutableData data];
[body appendData:[[NSString stringWithFormat:#"\r\n--%#\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithFormat:#"Content-Disposition: form-data; name=\"image\"; filename=\"ipodfile.jpg\"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithFormat:#"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[NSData dataWithData:imageData]];
[body appendData:[[NSString stringWithFormat:#"\r\n--%#--\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
// setting the body of the post to the reqeust
[request setHTTPBody:body];
Here is the code to fire request.
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue]
completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
NSLog(#"Finished with status code: %i", [(NSHTTPURLResponse *)response statusCode]);
}];
So How can i Calculate the Remaining time so that i can Show an indicator ?
Thanks for your time.

Answer 1

You can use this method of connection delegate:
- (void) connection:(NSURLConnection *)connection
didSendBodyData:(NSInteger)bytesWritten
totalBytesWritten:(NSInteger)totalBytesWritten
totalBytesExpectedToWrite:(NSInteger)totalBytesExpectedToWrite;
(How should I wrap such long argument names?)
It's not in documentation of NSURLConnectionDataDelegate, but if you check the public header NSURLConnection.h, it's there. So don't worry about using it.
From documentation URL Loading System Programming Guide > Using NSURLConnection:
Estimating Upload Progress
You can estimate the progress of an HTTP POST upload with the connection:didSendBodyData:totalBytesWritten:totalBytesExpectedToWrite: delegate method. Note that this is not an exact measurement of upload progress, because the connection may fail or the connection may encounter an authentication challenge.

Answer 2

I believe you want to show something like a progress bar. I recomend using the MKNetworkKit that provides you many tools for network management, such as progress of an asynchronous connection. Check this link.