Uitable view reloads 2x times OR view is pushed 2 times

Question

Hi!
I am not really sure whats happening.
Either my UITableView is reloading 2x, or the pushViewController is fired 2x times.
If I am pushing the view, it appears, but is pushed again and loads the rest..
any hints?
I did also remove all [view reloadData] commands..
my tableView is loading the data (XML Feed) in the viewDidLoad method.
if I am loading the data before pushing the tableView (therefore not within viewDidLoad), the table stays empty.

Answer 1

Hi Alex -
Methods like viewDidLoad, viewWillAppear and viewDidAppear can be called more than once during the same view transition, though in my experience the first is much less likely to repeat than the other two. In these cases, I sometimes use boolean instance vars to lock out any code that should only run once. E.g.:
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
if (!self.didAppear++) {
// init data and/or reload table view
NSLog(@"viewDidAppear");
- (void)viewDidDisappear:(BOOL)animated {
[super viewDidDisappear:animated];
self.didAppear = NO;
I'm not claiming this example is thread safe, though I'd only expect calls to come from the main thread. You might declare the boolean to be atomic if you tend to lose sleep over this type of question.
On the other hand, pushViewController will only run twice if your code calls it twice. I can't guess how you're managing to do this. For instance, didSelectRowAtIndexPath is pretty good about not repeating. So if you're seeing an extra, unintended push transition, it's fairly safe to assume something's wrong with your code. Logging can be a big help in a case like this. E.g.:
NSArray *stack = self.navigationController.viewControllers;
// place this before and after each call to push or pop ViewController:
NSLog(@"stack = %@", stack);
If the above doesn't provide any clues, we might be able to help more if you posted any transition-related code (e.g. for the controller calling push and the controller being pushed).
- Ray