iOS7在viewDidLoad和viewDidAppear之间暂停

Question

我想在viewDidLoad期间调用Web服务。在parserDidEnd只生成viewWillAppear后，这可能吗？

-(void)viewDidLoad{
    //call webservices
    //display LOADING INDICATOR
}

-(void)parserDidEndDocument:(NSXMLParser *)parser{
    //** What should I put here? **
}

-(void)viewWillAppear{
    //dismiss LOADING INDICATOR
    //continue to load screen.
}