iphone MBProgreeHUD Not worked When using POST method - objective-c

Question

When i will try to post some image or text from application to server that situation MBProgressHUD not worked. but without posting method its work perfectly. i am used below code.Please any one help me. thanks.
HUD = [MBProgressHUD showHUDAddedTo:self.view animated:YES];
HUD.dimBackground = YES;
HUD.delegate = self;
NSString *urlRequest =[NSString stringWithFormat:#"URL"];
NSString *pStrLegalURLString =[urlRequestn stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL *url = [[NSURL alloc] initWithString:pStrLegalURLString];
NSMutableURLRequest *request1 = [NSMutableURLRequest requestWithURL:url];
[request1 setHTTPMethod:#"POST"];
NSData *returnData1 = [ NSURLConnection sendSynchronousRequest: request1 returningResponse: nil error: nil ];
NSString *returnString1 = [[NSString alloc] initWithData:returnData1 encoding: NSUTF8StringEncoding];

Answer 1

Try like this:
It will work, but your problem as i guess is because of sendSynchronousRequest which is a blocking call hence if the main thread hangs up you won't see any update in UI. So try to make such calls in background.
Try one of the two approaches as I see:
Approach 1: (send request in background using selectors and do UI update in main thread)
-(void)method1 {
HUD = [MBProgressHUD showHUDAddedTo:self.view animated:YES];
HUD.dimBackground = YES;
HUD.delegate = self;
NSString *urlRequest =[NSString stringWithFormat:#"URL"];
NSString *pStrLegalURLString =[urlRequest stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL *url = [[NSURL alloc] initWithString:pStrLegalURLString];
NSMutableURLRequest *request1 = [NSMutableURLRequest requestWithURL:url];
[request1 setHTTPMethod:#"POST"];
// send request in background.
[self performSelectorInBackground:#selector(method2) withObject:nil];
}
-(void)method2 {
NSData *returnData1 = [ NSURLConnection sendSynchronousRequest: request1 returningResponse: nil error: nil ];
NSString *returnString1 = [[NSString alloc] initWithData:returnData1 encoding: NSUTF8StringEncoding];
[self performSelectorOnMainThread:#selector(method3) withObject:nil waitUntilDone:NO];
}
-(void)method3
{
// update ui in main thread.
[MBProgressHUD hideAllHUDsForView:self.view animated:YES];
}
Approach 2: Use Dispatch_Async and Dispatch_Sync
dispatch_async(dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), ^(void){
// Do background work here
dispatch_sync(dispatch_get_main_queue(), ^(void){
// Update UI here
});
});