Get URL File Size before parsing - iphone

Question

Me again! I am using NSURL to get a file then parse it. I have been looking for a couple of hours now on a progressbar i am trying to implement in my app. I know I first need to get the file size, then keep updating how much data i've downloaded as I continue to pull. I have seen the example using "ASIHTTPRequest" but is there a way to do it with what I already have?
Here is where I start the download.
-(void)parseNewData {
//start network activity spinner and release controller when done
parserDone = NO;
[root downloadIcon];
//create pool to avoid memory leak
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
// get the XML path and start parsing
NSURL *pathURL = [NSURL URLWithString:#"http://www.mysite.com/myfile.xml"];
NSXMLParser *parser = [[NSXMLParser alloc] initWithContentsOfURL:pathURL];
[parser setDelegate:self];
[parser parse];
//drain pool
[pool drain];
[pool release];
}
Can someone point me in the right direction on how to get file size, then how to update how much I've downloaded. Thanks in advance!

Answer 1

-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
[webData setLength: 0];
CGFloat size = [[NSString stringWithFormat:#"%lli",[response expectedContentLength]] floatValue];
NSLog(#"Size : %f",size);
}
Above code will give you total size
-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
[webData appendData:data];
totalDownloadedData += [data length]; // global integer
NSLog(#"Status : %d/%f",totalDownloadedData,size);
}
Above code will show you current status of downloading

Answer 2

You need to use NSURLConnection if you want to get the file size and the progress. You get delegate methods which you can use to monitor progress. The didSendBodyData: delegate method tells you how much data there is in bytes. The connectionDidFinishLoading is where you uget receivedData to use in your NSXMLParser code.
NSURLRequest *theRequest = [NSURLRequest requestWithURL:URL cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10.0];
NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:theRequest delegate:self];
if (theConnection) {
receivedData = [[NSMutableData data] retain];
}
}
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response{
// This method is called when the server has determined that it
// has enough information to create the NSURLResponse.
// It can be called multiple times, for example in the case of a
// redirect, so each time we reset the data.
// receivedData is an instance variable declared elsewhere.
[receivedData setLength:0];
}
- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error{
// release the connection, and the data object
// inform the user
NSLog(#"Connection failed! Error - %# %#",
[error localizedDescription],
[[error userInfo] objectForKey:NSErrorFailingURLStringKey]);
[connection release];
// receivedData is declared as a method instance elsewhere
[receivedData release];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data{
// Append the new data to receivedData.
// receivedData is an instance variable declared elsewhere.
[receivedData appendData:data];
}
- (void)connection:(NSURLConnection *)connection didSendBodyData:(NSInteger)bytesWritten totalBytesWritten:(NSInteger)totalBytesWritten totalBytesExpectedToWrite:(NSInteger)totalBytesExpectedToWrite{
- (void)connectionDidFinishLoading:(NSURLConnection *)connection{