UITableView items not showing - ios

Question

I have a UITableView which reads items from an NSMutableArray called friendsList.
I initialise this array here:
- (id)initWithCoder:(NSCoder *)aDecoder
{
self = [super initWithCoder:aDecoder];
if (self) {
self.title = TA(#"Find Friends", #"");
self.navigationItem.rightBarButtonItem = [self createRightNavBarButton];
self.navigationItem.leftBarButtonItem = [self createLeftNavBarButton];
friendsList = [[NSMutableArray alloc]init];
}
return self;
}
I have set it's datasource method for numberOfRows to return friendslist.count if the count is greater than zero.
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
if (friendsList.count) {
return friendsList.count;
}
else{
return 0;
}
}
After I fill the array in another method I'm calling [tableView reloadData] so that the datasource method is called again to read the count of the objects in the array.
- (void)loadContactsFromSource:(ListSource)source
{
if (friendsList) {
[friendsList removeAllObjects];
}
switch (source) {
case LS_Facebook:
break;
case LS_Twitter:
break;
case LS_Contacts:{
ABAddressBookRef addressBook = ABAddressBookCreateWithOptions(nil, nil);
ABAddressBookRequestAccessWithCompletion(addressBook, ^(bool granted, CFErrorRef error) {
if (granted) {
CFArrayRef allPeople = ABAddressBookCopyArrayOfAllPeople( addressBook );
CFMutableArrayRef peopleMutable = CFArrayCreateMutableCopy(
kCFAllocatorDefault,
CFArrayGetCount(allPeople),
allPeople
);
CFArraySortValues(
peopleMutable,
CFRangeMake(0, CFArrayGetCount(peopleMutable)),
(CFComparatorFunction) ABPersonComparePeopleByName,
(void*) ABPersonGetSortOrdering()
);
CFIndex nPeople = ABAddressBookGetPersonCount( addressBook );
for ( int i = 0; i < nPeople; i++ )
{
ABRecordRef ref = CFArrayGetValueAtIndex(peopleMutable, i);
[self copyContactToArray:ref];
}
[tableFriends reloadData];
}
else{
[PopupHandler popupDialogWithTitle:T(#"Error", #"")
message:T(#"Access denied", #"")
delegate:nil];
}
});
break;
}
default:
break;
}
}
Here is the cellForRow method:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (!cell) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
}
NSDictionary *currentPerson = [friendsList objectAtIndex:indexPath.row];
cell = [self fillCell:cell withUserInfo:currentPerson];
return cell;
}
The problem is that after this table remains blank, the items from the array are not show. If I touch the table with my finger the items show up instantly, as if the touch somehow refreshes the table. Any ideas what might be causing this?
I'm testing this on an iPhone 5 with iOS 7, built from XCode 5.0.1 .

Answer 1

It looks like ABAddressBookRequestAccessWithCompletion is being called on a separate thread and the block that it runs when completed is not in the main thread. So updating the UI inside the block will not work properly. Try either creating a function and calling that function on the main thread from inside your addressbook return or doing a dispatch_async inside the addressbook return block.
Inside your return block from ABAddressBookRequestAccessWithCompletion dispatch into the main thread by either using dispatch_async or performSelectorOnMainThread.