Populating Core Data into Table View - ios

Question

I am trying to display data in a custom tableview. Idea is that in ViewController A i populate data into the Core Data entity, in ViewController B I retrieve data from Core Data entity successfully and display it in table view with no problem. Here comes the problem. If I delete data from entity and tableview in ViewController B, go back to ViewController A and add new item to Core Data again, it does not appear in tableview when I go back to ViewController B. But if i close and open the application again, the item appears there again.
So the problem is that the item appear in core data after deleting an item and inserting again, but doesnt appear in tableview. Maybe i have to update tableview somehow, but i tried [self.tableview reloadData]; and it did not help. Code Below. Any Ideas???
ViewController A
#import "ListItem.h"
#import "ViewOrders.h"
#import "MainView.h"
#import "Order_list.h"
#import "AppDelegate.h"
#interface ListItem ()
#property (nonatomic, strong) NSManagedObjectContext *managedObjectContext;
#property (nonatomic, retain) NSFetchedResultsController *results;
#property (nonatomic, strong) NSMutableArray *namesArray;
#property (nonatomic, strong) NSMutableArray *quantityArray;
#property (nonatomic, strong) NSMutableArray *priceArray;
#property (nonatomic, strong) NSMutableArray *imagesArray;
#end
#implementation ListItem
#synthesize managedObjectContext = _managedObjectContext;
#synthesize results = _results;
#synthesize imageView = _imageView;
#synthesize mainView = _mainView;
#synthesize nameField = _nameField;
#synthesize descField = _descField;
#synthesize priceField = _priceField;
#synthesize quantityField = _quantityField;
#synthesize quantityStepperOutlet = _quantityStepperOutlet;
#synthesize namesArray =_namesArray;
#synthesize quantityArray = _quantityArray;
#synthesize priceArray = _priceArray;
#synthesize imagesArray = _imagesArray;
- (void)viewDidLoad
{
[super viewDidLoad];
AppDelegate *delegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
self.managedObjectContext = delegate.managedObjectContext;
//self.navigationItem.hidesBackButton = YES;
self.namesArray = [[NSMutableArray alloc] init];
self.quantityArray = [[NSMutableArray alloc] init];
self.priceArray = [[NSMutableArray alloc] init];
self.imagesArray = [[NSMutableArray alloc] init];
UIGraphicsBeginImageContext(self.view.frame.size);
[[UIImage imageNamed:#"bella_italia_crop.png"] drawInRect:self.view.bounds];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
self.view.backgroundColor = [UIColor colorWithPatternImage:image];
UIGraphicsBeginImageContext(self.mainView.frame.size);
[[UIImage imageNamed:#"bella_italia_crop.png"] drawInRect:self.mainView.bounds];
UIImage *image2 = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
self.mainView.backgroundColor = [UIColor colorWithPatternImage:image2];
self.imageView.image = [UIImage imageNamed:self.thumbnail];
self.imageView.contentMode = UIViewContentModeScaleAspectFit;
self.nameField.text = self.name;
self.descField.text = self.description;
self.priceField.text = self.price;
self.descField.backgroundColor = [UIColor clearColor];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([segue.identifier isEqualToString:#"viewAllOrdersSegue"])
{
ViewOrders *vo = segue.destinationViewController;
vo.namesArray = self.namesArray;
vo.quantityArray = self.quantityArray;
vo.priceArray = self.priceArray;
vo.tableNumber = #"1";
vo.imagesArray = self.imagesArray;
}
else if ([segue.identifier isEqualToString:#"unwindToMain"])
{
MainView *mv = segue.destinationViewController;
mv.namesArray = self.namesArray;
mv.quantityArray = self.quantityArray;
mv.priceArray = self.priceArray;
mv.imagesArray = self.imagesArray;
}
}
- (IBAction)quantityStepper:(UIStepper *)sender
{
int stepper = [sender value];
self.quantityField.text = [NSString stringWithFormat:#"%d", stepper];
}
- (IBAction)addOrderAction:(UIButton *)sender
{
NSLog(#"Add order action button pressed");
Order_list *newItem = [NSEntityDescription insertNewObjectForEntityForName:#"Order_list" inManagedObjectContext:self.managedObjectContext];
newItem.title = self.name;
newItem.quantity = #([self.quantityField.text floatValue]);
newItem.price = #([self.priceField.text floatValue]);
newItem.tableNumber = [NSNumber numberWithInt:1];
newItem.thumbnail = self.thumbnail;
newItem.id = [NSNumber numberWithInt:0];
NSError *error;
[self.managedObjectContext save:&error];
UIAlertView *successAlert = [[UIAlertView alloc] initWithTitle:#"Success!" message:#"Your order was successfully added to orders list! Press View Orders to finalize the order or go back to menu and choose something else." delegate:self cancelButtonTitle:#"Ok" otherButtonTitles:nil, nil];
successAlert.alertViewStyle = UIAlertViewStyleDefault;
[successAlert show];
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:#"Order_list" inManagedObjectContext:self.managedObjectContext];
[fetchRequest setEntity:entity];
NSArray *fetchedObjects = [self.managedObjectContext executeFetchRequest:fetchRequest error:&error];
for (NSManagedObjectContext *info in fetchedObjects) {
NSLog(#"Title: %# %#", [info valueForKey:#"title"], [info valueForKey:#"quantity"]);
}
//[self.namesArray addObject:self.name];
//[self.quantityArray addObject:self.quantityField.text];
//int finalPrice = [self.quantityField.text intValue] * [self.price intValue];
//[self.priceArray addObject:[NSString stringWithFormat:#"%d", finalPrice]];
//[self.imagesArray addObject:self.thumbnail];
//NSLog(#"Names: %#, Quantities: %#, Prices: %#", self.namesArray, self.quantityArray, self.priceArray);
}
#end
ViewController B
#import "ViewOrders.h"
#import "AppDelegate.h"
#import "Order_list.h"
#import "ViewOrdersCell.h"
#interface ViewOrders ()
#property (nonatomic, strong) NSMutableData *requestData;
#property (nonatomic, strong) NSManagedObjectContext *managedObjectContext;
#property (nonatomic, retain) NSFetchedResultsController *results;
#property (nonatomic, strong) NSString* orderState;
#property (nonatomic, strong) UIAlertView *billAlert;
#end
#implementation ViewOrders
#synthesize managedObjectContext = _managedObjectContext;
#synthesize results = _results;
#synthesize confirmOrderButton = _confirmOrderButton;
#synthesize requestData = _requestData;
#synthesize orderState = _orderState;
#synthesize billAlert = _billAlert;
- (void)viewDidLoad
{
[super viewDidLoad];
self.billAlert = [[UIAlertView alloc] initWithTitle:#"Order Confirmed!" message:#"Your order list has been successfully confirmed and is sent to kitchen! Press Request Bill Now or Request Bill Later to Continue (You cannot make any new orders until you request a bill for current one! To trigger this screen again, press and hold on any order in pending orders page. Thanks!)" delegate:self cancelButtonTitle:#"Request Bill Later" otherButtonTitles:#"Request Bill Now", nil];
self.billAlert.tag = 2;
self.billAlert.alertViewStyle = UIAlertViewStyleDefault;
AppDelegate *delegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
self.managedObjectContext = delegate.managedObjectContext;
self.namesArray = [[NSMutableArray alloc] init];
self.quantityArray = [[NSMutableArray alloc] init];
self.imagesArray = [[NSMutableArray alloc] init];
self.priceArray = [[NSMutableArray alloc] init];
NSFetchRequest *coreRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:#"Order_list" inManagedObjectContext:self.managedObjectContext];
[coreRequest setEntity:entity];
NSSortDescriptor *sort = [[NSSortDescriptor alloc] initWithKey:#"title" ascending:YES];
[coreRequest setSortDescriptors:[NSArray arrayWithObject:sort]];
[coreRequest setFetchBatchSize:20];
NSFetchedResultsController *controller = [[NSFetchedResultsController alloc] initWithFetchRequest:coreRequest managedObjectContext:self.managedObjectContext sectionNameKeyPath:nil cacheName:#"Root"];
self.results = controller;
self.results.delegate = self;
NSError *error;
[self.results performFetch:&error];
NSArray *fetchedObjects = [self.managedObjectContext executeFetchRequest:coreRequest error:&error];
for (NSManagedObjectContext *info in fetchedObjects)
{
self.orderState = [NSString stringWithFormat:#"%#", [info valueForKey:#"id"]];
[self.namesArray addObject:[info valueForKey:#"title"]];
[self.quantityArray addObject:[info valueForKey:#"quantity"]];
[self.imagesArray addObject:[info valueForKey:#"thumbnail"]];
[self.priceArray addObject:[info valueForKey:#"price"]];
//NSLog(#"List: %#", [info valueForKey:#"title"]);
}
if ([self.orderState isEqualToString:#"1"])
{
self.confirmOrderButton.enabled = false;
}
//self.navigationController.navigationItem.backBarButtonItem.enabled = false;
//self.navigationItem.hidesBackButton = YES;
// Uncomment the following line to preserve selection between presentations.
// self.clearsSelectionOnViewWillAppear = NO;
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem;
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
id sectionInfo = [[self.results sections] objectAtIndex:section];
return [sectionInfo numberOfObjects];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
//UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"ordersCell" forIndexPath:indexPath];
ViewOrdersCell *cell = [tableView dequeueReusableCellWithIdentifier:#"ordersCell" forIndexPath:indexPath];
cell.title.text = [self.namesArray objectAtIndex:indexPath.row];
cell.thumbnail.image = [UIImage imageNamed:[self.imagesArray objectAtIndex:indexPath.row]];
cell.status.text = #"Waiting to Confirm";
if ([self.orderState isEqualToString:#"0"])
{
cell.status.text = #"Waiting to Confirm";
cell.status.textColor = [UIColor redColor];
}
else
{
cell.status.textColor = [UIColor greenColor];
cell.status.text = #"Confirmed";
}
UILongPressGestureRecognizer *longPressRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:#selector(onLongPress:)];
[cell addGestureRecognizer:longPressRecognizer];
//cell.textLabel.text = [self.namesArray objectAtIndex:indexPath.row];
//cell.imageView.image = [UIImage imageNamed:[self.imagesArray objectAtIndex:indexPath.row]];
//cell.backgroundColor = [UIColor clearColor];
return cell;
}
// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
return YES;
}
// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
if (editingStyle == UITableViewCellEditingStyleDelete)
{
// Delete the row from the data source
NSManagedObject *managedObject = [self.results objectAtIndexPath:indexPath];
[self.managedObjectContext deleteObject:managedObject];
[self.managedObjectContext save:nil];
//[tableView deleteRowsAtIndexPaths:#[indexPath] withRowAnimation:UITableViewRowAnimationFade];
//[tableView reloadRowsAtIndexPaths:#[indexPath] withRowAnimation:UITableViewRowAnimationFade];
}
}
- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller
{
[self.tableView beginUpdates];
}
- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller
{
[self.tableView endUpdates];
}
- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type newIndexPath:(NSIndexPath *)newIndexPath {
if (type == NSFetchedResultsChangeInsert)
{
[self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
}
if (type == NSFetchedResultsChangeDelete)
{
[self.tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
}
if (type == NSFetchedResultsChangeUpdate)
{
}
if (type == NSFetchedResultsChangeMove)
{
[self.tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
[self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
}
}
- (void)controller:(NSFetchedResultsController *)controller didChangeSection:(id<NSFetchedResultsSectionInfo>)sectionInfo atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type
{
if (type == NSFetchedResultsChangeInsert)
{
[self.tableView insertSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade];
}
if (type == NSFetchedResultsChangeDelete)
{
[self.tableView deleteSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade];
}
}
/*
// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
{
}
*/
/*
// Override to support conditional rearranging of the table view.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
// Return NO if you do not want the item to be re-orderable.
return YES;
}
*/
#pragma mark - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
// Get the new view controller using [segue destinationViewController].
// Pass the selected object to the new view controller.
}
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if(buttonIndex == 1 && alertView.tag == 1)
{
NSLog(#"Confirm Pressed");
//////Send Order to the Server//////
NSFetchRequest *fetchRequest = [NSFetchRequest fetchRequestWithEntityName:#"Order_list"];
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"id=0"];
fetchRequest.predicate = predicate;
NSError *error = nil;
NSArray *array = [self.managedObjectContext executeFetchRequest:fetchRequest error:&error];
for (NSManagedObjectContext *info in array)
{
NSNumber *temp = [[NSNumber alloc] initWithInt:1];
[info setValue:temp forKey:#"id"];
}
[self.managedObjectContext save:&error];
[self.tableView reloadData];
self.confirmOrderButton.enabled = false;
[self.billAlert show];
}
else if (buttonIndex == 1 && alertView.tag == 2)
{
self.confirmOrderButton.enabled = true;
UIAlertView *billRequest = [[UIAlertView alloc] initWithTitle:#"Bill Request Successful!" message:#"Your bill has been requested successfully! Waiter will deliver it to you as soon as possible! Thanks for visiting Bella Italia!" delegate:self cancelButtonTitle:#"Ok" otherButtonTitles:nil, nil];
billRequest.alertViewStyle = UIAlertViewStyleDefault;
billRequest.tag = 3;
[billRequest show];
NSFetchRequest *fetchItems = [[NSFetchRequest alloc] init];
[fetchItems setEntity:[NSEntityDescription entityForName:#"Order_list" inManagedObjectContext:self.managedObjectContext]];
[fetchItems setIncludesPropertyValues:NO]; //only fetch the managedObjectID
NSError *error = nil;
NSArray *array = [self.managedObjectContext executeFetchRequest:fetchItems error:&error];
[self.results performFetch:&error];
//error handling goes here
for (NSManagedObject *item in array)
{
[self.managedObjectContext deleteObject:item];
}
NSError *saveError = nil;
[self.managedObjectContext save:&saveError];
}
else if (buttonIndex == 0 && alertView.tag == 2)
{
}
else if (buttonIndex == 0 && alertView.tag == 3)
{
[self.navigationController popToRootViewControllerAnimated:UITableViewRowAnimationFade];
}
}
- (IBAction)confirmOrder:(UIBarButtonItem *)sender
{
NSLog(#"Confirm Order");
UIAlertView *confOrder = [[UIAlertView alloc] initWithTitle:#"Confirm Order!" message:#"This will send your order to process. Once this is done, no more changes are available. Are you sure you want to confirm your order?" delegate:self cancelButtonTitle:#"Cancel" otherButtonTitles:#"Confirm", nil];
confOrder.alertViewStyle = UIAlertViewStyleDefault;
confOrder.tag = 1;
[confOrder show];
}
-(void)onLongPress:(UILongPressGestureRecognizer*)pGesture
{
NSLog(#"Long Press");
[self.billAlert show];
}
#end
EDIT
Forgot to mention that i am using Custom Cell. Maybe that affects the situation somehow?
I tried to NSLog the variables which store the data that supposed to appear in tableview. All the data is beeing passed, but it does not appear in tableview. Logically [self.tableView reloadData in viewWillAppear should do the trick, but it does not........

Answer 1

I have a similar setup in one my apps and I add an observer to the ViewController with the table that wants updating;
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(reload) name:#"UpdatedCoreData" object:nil];
I clear any arrays or dictionaries I use in the reload method and call (inside my async queue);
[self.tableView performSelectorOnMainThread:#selector(reloadData) withObject:nil waitUntilDone:NO];
Then when I finish updating the core data in my other VC I call it;
[[NSNotificationCenter defaultCenter] postNotificationName:#"UpdatedCoreData" object: nil];
And that works perfectly fine for me, I don't know if that will help you at all.
EDIT:
Along the lines of my reload method;
- (void)reload {
// Do any potential clean up if neccesary
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_async(queue, ^{
// Fetch core data & populate dictionaries/arrays
[self.tableView performSelectorOnMainThread:#selector(reloadData) withObject:nil waitUntilDone:NO];
});
}