Loading Image into UIImageView using NSURLConnection - iphone

Question

Hey all. I'm really new at this obj-c/xcode stuff. I'm trying to load the background of my xib file. To do this i'm using a UIImageView and populating that with an image I found from the net. the problem with that is that it's REALLY slow. Feels like it's crashing but it's not. I was told to use an NSURLConnection to fix the problem but don't know how. Here's the code i was using previously.
wallpaper.image = [UIImage imageWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:[NSString stringWithFormat:#"http://mysite.com/mobile/wallpaperR.asp?id=%i",customerID]]]];
How do i translate the above code into the NSURLConnection equivalent?

Answer 1

NSURLConnection will download the data in a new thread, so you app will feel much faster.
It is pretty easy to implement but it does require you to understand the concept of delegation.
I have a useful class I created to handle image downloads on separate threads, I will share the code with you, with comments to let you know what is going on:
AsyncImage.h
AsyncImage.m
If you need help implementing it just leave a comment and I can help you get it working, I remember this used to be pain for me too when I started developing.

Answer 2

You need to do parsing for this as you are using the webservice.Like this
-(void)startParsingForPhotoAlbumList:(NSString*)providerIdString
{
NSString *urlString = [NSString stringWithFormat:#"http://YourUrl/showalbumxml.php?id=%#&show=show",providerIdString];
NSURL *xmlURL = [NSURL URLWithString:urlString];
NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] initWithURL:xmlURL cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:30.0]autorelease];
NSURLResponse *returnedResponse = nil;
NSError *returnedError = nil;
NSData *itemData = [NSURLConnection sendSynchronousRequest:request returningResponse:&returnedResponse error:&returnedError];
self.xmlParser = [[NSXMLParser alloc] initWithData:itemData];
[xmlParser setDelegate:self];
[xmlParser parse];
}
and need to implement parser's delegate method as an example.
- (void)parserDidEndDocument:(NSXMLParser *)parser
{
if ([[[resultArray objectAtIndex:1]objectForKey:#"Transaction"]isEqualToString:#"Myapp/snaps"])
{
[(LoginViewController *)obj getRegisterResult:resultArray];
}
}
Then in your Viewcontroller access the data,from parsing you need to pass objects,using array or dictionary.
NSData *imageData = [NSData dataWithContentsOfURL:[NSURL URLWithString:itemImagePath]];
UIImage *image = [[UIImage alloc] initWithData:imageData];

Answer 3

There is an example which may help:
NSURLConnection loading image example