ASIFormDataRequest 进度条控制

ASIFormDataRequest*request =[ASIFormDataRequest requestWithURL:url];

[request setPostValue:someValue forKey:@"someKey"];
[request setPostValue:someOtherValue forKey:@"someOtherKey"];
[request setShowAccurateProgress:YES];
[request setDownloadProgressDelegate:aProgressView];

request.delegate = self;
[request startSynchronous];