Question

I’m trying to upload images to a php file, everything works, but sometimes when the site is

getting slow to load our app start frizzing until the page is done loading so i thought

about using threads to avoid such frizzing, but right now our app display and quit. I dont

see any warnings or problem… it just enter the app and exist right away. Please help me

out

the code:

-(void) source {
    NSData *imageData = UIImageJPEGRepresentation(imageView.image, 80);

    NSString *urlString = @"http://domain";

    NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
    [request setURL:[NSURL URLWithString:urlString]];
    [request setHTTPMethod:@"POST"];


    our_label.text = [NSString stringWithFormat:@"%@", returnString];
}


-(void)som:(id)param{
    [lock lock];

    [lock unlock];
}

Answer 1

You can use the NSURLRequest in an asynch method, however if you want your current code to work follow these insturctions

First change this line

[NSThread detachNewThreadSelector:@selector(multithreading:) toTarget:  [MainViewController class] withObject:nil];

to

[NSThread detachNewThreadSelector:@selector(multithreading:) toTarget:self withObject:nil];

Second, you are updating the UI in a non UI thread, so wrap this

our_label.text = [NSString stringWithFormat:@"%@", returnString];

around dispatch_get_main_queue like the following

dispatch_async(dispatch_get_main_queue(), ^{
    our_label.text = [NSString stringWithFormat:@"%@", returnString];
});

Finally remove the locks since you are not really using them

    //[lock lock];
    [self source];
    //[lock unlock];