IOS: how can i refresh UI with async TBXML-call - objective-c

Question

I'm using TBXML to parse an http-XML file and display the contents in a UILabel & UIImageView .
The call to the XML is done with an async request.
When i view the logs the last log element in the succesblock is printed immediately. The changes in the UILabel & UIImageview are only visible after a few seconds.
How can i let IOS refresh the UI straight after finishing processing the XML ?
// Create a success block to be called when the async request completes
TBXMLSuccessBlock successBlock = ^(TBXML *tbxmlDocument) {
// If TBXML found a root node, process element and iterate all children
NSLog(#"PROCESSING ASYNC CALLBACK");
if (tbxmlDocument.rootXMLElement)
[self traverseElement:tbxmlDocument.rootXMLElement];
myArticle.Body = [[StringCleaner sharedInstance] cleanedString:myArticle.Body];
// myArticle.Body = [myArticle.Body stringByConvertingHTMLToPlainText];
self.articleBody.text = myArticle.Body;
self.articleBody.numberOfLines= 0;
self.articleBody.lineBreakMode = UILineBreakModeWordWrap;
[self.articleBody sizeToFit];
// set scroll view size
self.articleBodyScrollView.contentSize = CGSizeMake(self.articleBodyScrollView.contentSize.width, self.articleBody.frame.size.height);
NSURL *url = [NSURL URLWithString:myArticle.Photo];
NSData *data = [NSData dataWithContentsOfURL:url];
if (data != NULL)
{
UIImage *image = [UIImage imageWithData:data];
// articlePhoto = [[UIImageView alloc] initWithImage:image];
[self.articlePhoto setImage:image];
}else {
NSLog(#"no data");
}
NSLog(#"FINISHED PROCESSING ASYNC");
// [self printArticles];
};
// Create a failure block that gets called if something goes wrong
TBXMLFailureBlock failureBlock = ^(TBXML *tbxmlDocument, NSError * error) {
NSLog(#"Error! %# %#", [error localizedDescription], [error userInfo]);
};
// tbxml = [[TBXML alloc] initWithURL:[NSURL URLWithString:someXML]];
tbxml = [[TBXML alloc] initWithURL:[NSURL URLWithString:records]
success:successBlock
failure:failureBlock];

Answer 1

Sounds like your trying to update UI but not on UI thread. Wrap your UILabel and UIImageView updates into a dispatch_async on the main thread, e.g.:
dispatch_async(dispatch_get_main_queue(), ^
{
[self.articlePhoto setImage:image];
});