Update TableView after adding CoreData - ios

Question

I'm working on a CoreData App which displays the content of the CoreData in a TableView.
The Problem is, after adding a string the tableView is not Updating the Content of the CoreData.
i tried it with:
- (void)viewWillAppear:(BOOL)none
{
[self.tableView reloadData];
}
But no Chance, its not reloading.
Any guesses or should I post some more Code? thank you :)
So more Code :)
Saving string to CoreData:
- (void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
AppDelegate *appDelegate =
[[UIApplication sharedApplication] delegate];
NSManagedObjectContext *context =
[appDelegate managedObjectContext];
NSManagedObject *newProduct;
newProduct = [NSEntityDescription
insertNewObjectForEntityForName:#"Products"
inManagedObjectContext:context];
[newProduct setValue: _textField.text forKey:#"productName"];
NSError *error;
[context save:&error];
NSLog(#"Product saved");
}
And the Code of the TableViewController:
#implementation CartViewController
- (id)initWithStyle:(UITableViewStyle)style
{
self = [super initWithStyle:style];
if (self) {
// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
//Core Data Versuche
/*
Fetch existing events.
Create a fetch request for the Event entity; add a sort descriptor; then execute the fetch.
*/
NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:#"Products"];
[request setFetchBatchSize:20];
// Order the events by creation date, most recent first.
// NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:#"creationDate" ascending:NO];
// NSArray *sortDescriptors = #[sortDescriptor];
// [request setSortDescriptors:sortDescriptors];
// Execute the fetch.
NSError *error;
AppDelegate *delegate = (AppDelegate*)[[UIApplication sharedApplication] delegate];
NSArray *fetchResult = [delegate.managedObjectContext executeFetchRequest:request error:&error];
if (fetchResult== nil) {
// Replace this implementation with code to handle the error appropriately.
// abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
NSLog(#"Unresolved error %#, %#", error, [error userInfo]);
}
// Set self's events array to a mutable copy of the fetch results.
[self setCartProductsArray:[fetchResult mutableCopy]];
/*
Reload the table view if the locale changes -- look at APLEventTableViewCell.m to see how the table view cells are redisplayed.
*/
__weak UITableViewController *cell = self;
[[NSNotificationCenter defaultCenter] addObserverForName:NSCurrentLocaleDidChangeNotification object:nil queue:[NSOperationQueue mainQueue] usingBlock:^(NSNotification *note) {
[cell.tableView reloadData];
}];
// Ende Core Data Versuche
}
- (void)viewWillAppear:(BOOL)none
{
[self.tableView reloadData];
}

Answer 1

What you probably want to do is use an NSFetchedResultsController.
Make sure that when you are updating the data, you are really just updating CoreData.
When things change in CoreData and you have an NSFetchedResultsController you can subscribe to updates. Apple has great documentation on how to make this work. These updates will update your table correctly using the delegation methods. This ends up mostly being a copy and paste from the documentation.