Calling UITableView's reloadData method from appdelegate - ios

Question

I am having a serious issue with UITableView reloadData method. I have a UIViewController class, WiGiMainViewController that has a UITableView and NSMuttableArray in it. I am currently issuing network calls in the AppDelegate, and posting notifications to the WiGiMainViewController once the data has been downloaded. In my selector method for the notification, reloadWigiList, I am passing an NSArray containing the the recently downloaded items. I then initialize the WiGiMainViewController's NSMuttableArray with the passed in array and proceed to call reloadData() on my UITableView object. I can see from nslog statements that the numberOfRowsInSection is fired on reload but not the cellForRowAtIndexPath, therefore causing the UI NOT to reload the UITableView with the newly downloaded items. I have verified that the reloadData method is being called on the main thread and that the datasource delegate are set in IB and programatically in the viewDidLoad method of WiGiMainViewController. Any ideas why my UITableView, wigiLists isn't reloading the data, in particular, not calling the cellForRowAtIndexPath method?
#interface WiGiMainViewController : UIViewController<FBRequestDelegate,UITableViewDelegate, UITableViewDataSource> {
//setup UI
UITableView *wigiLists;
WiGiAppDelegate *myAppDelegate;
NSMutableArray *itemsList;
}
#property (nonatomic, retain) WiGiAppDelegate *myAppDelegate;
#property (nonatomic, retain) IBOutlet UITableView *wigiLists;
#property (nonatomic, retain) NSMutableArray *itemsList;
-(void) reloadWigiList: (NSNotification*) notification;
-(NSInteger) numberOfSectionsInTableView:(UITableView *)tableView;
-(NSInteger) tableView: (UITableView*) tableView numberOfRowsInSection:(NSInteger) section;
-(UITableViewCell *) tableView: (UITableView*)tableView cellForRowAtIndexPath: (NSIndexPath *)indexPath;
#end
#implementation WiGiMainViewController
#synthesize headerLabel = _headerLabel, userNameLabel = _userNameLabel, facebookPicture = _facebookPicture,
myAppDelegate, wigiLists, itemsList;
- (void)viewDidLoad {
NSLog(#"In viewDidLoad");
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(reloadWigiList:) name:#"wigiItemUpdate" object:nil];
// get appdelicate
self.myAppDelegate = (WiGiAppDelegate*) [[UIApplication sharedApplication] delegate];
self.itemsList = [[NSMutableArray alloc] init];
//setup tableview
self.wigiLists = [[UITableView alloc] initWithFrame:CGRectZero style:UITableViewStylePlain];
self.wigiLists.delegate = self;
self.wigiLists.dataSource = self;
//set up view
[self.headerLabel setText:self.myAppDelegate.HEADER_TEXT];
//check if user is logged in
if (self.myAppDelegate.isLoggedIn) {
//user is logged in
NSLog(#"HERE");
//get facebook information to populate view
[self retrieveFacebookInfoForUser];
//[self.myAppDelegate retrieveWigiItems];
}else {
//user is not logged in
NSLog(#"user not logged in");
//show login modal
}
//[self.wigiLists reloadData];
[super viewDidLoad];
}
-(void) reloadWigiList: (NSNotification *) notification {
if ([NSThread isMainThread]) {
NSLog(#"main thread");
}else{
NSLog(#"METHOD NOT CALLED ON MAIN THREAD!");
}
NSLog(#"notification recieved:%#", notification.userInfo);
NSLog(#"in reloadwigilists:%#", wigiLists );
NSLog(#"list size:%#", self.itemsList);
NSLog(#"delegate:%#",self.wigiLists.delegate);
NSLog(#"datasource:%#",self.wigiLists.dataSource);
//populate previously empty itemsList
[self.itemsList setArray:notification.userInfo];
NSLog(#"list size:%#", self.itemsList);
[self.wigiLists reloadData];
}
/////////////////////////////////////
// UITableViewDelegate protocols
-(NSInteger) numberOfSectionsInTableView:(UITableView *)tableView {
//NSLog(#"numberofsections: %#", [self.itemsList count]);
return 1;
}
-(NSInteger) tableView: (UITableView *)tableView numberOfRowsInSection:(NSInteger) section {
NSLog(#"7t87giuiu%#",self.itemsList);
NSLog(#"numberofrows: %i", [self.itemsList count]);
return [self.itemsList count];
//return 6;
}

Answer 1

first thing i would do is set a breakpoint on [self.wigiMainViewController.wigiLists reloadData]
if the wigiLists tableView shows a null in the debugger then it is probably an outlet that hasn't been set. also, make sure that both the delegate and datasource have been set.

Answer 2

Wow! after 3 days of banging my head against this problem, it was something ridiculously simple. In my ViewDidLoad method of WiGiMainViewController, i was initializing my tableview:
self.wigiLists = [[UITableView alloc] initWithFrame:CGRectZero style:UITableViewStylePlain];
Because I had linked the tableView I created in IB to my instance wigiLists, alloc'ing and initializing in the ViewDidLoad overwrote my link to the tableView created in IB and currently being displayed. Getting rid of this line fixed everything.