在动态tableview中显示单元格的总和

Question

我遇到了一个问题，我确信很多ObjectiveC开发人员都能轻松解决。我正在开发一个应用程序，它是一个动态的表视图，具有用户可以创建的不同组。用户可以输入具有不同总数的多个组。我试图总结所有创建的组。

我用来计算小计的IBAction是

- (IBAction)Calculate:(id)sender {
//---------------

NSInteger Tempsum = [[_dataArray valueForKeyPath:@"@sum.name2"] integerValue];


_TotalAnimals.text = [[NSString alloc] initWithFormat:@"%.1ld", (long)Tempsum];

//--------------

}

我在tableview的.m文件中创建了以下代码，并创建了一个名为的NSArray属性; @property NSArray * dataArray;

但我不确定使用正确的代码将结果（@“@ sum.name2”）链接到Tableviewcontroller中的文本值（_TotalAnimals.text）

非常感谢任何有关此问题的帮助。下面是.m文件的完整代码

#import "TSPViewController.h"
#import <CoreData/CoreData.h>

#import "TSPToDoCell.h"
#import "TSPAddToDoViewController.h"
#import "TSPUpdateToDoViewController.h"

int TempTotalAnimals = 0;
int TotalAnimals = 0;
int Tempsum = 0;


@interface TSPViewController () <NSFetchedResultsControllerDelegate>


@property (strong, nonatomic) NSFetchedResultsController *fetchedResultsController;
@property (strong, nonatomic) NSIndexPath *selection;
@property NSArray *dataArray;


@end

@implementation TSPViewController

#pragma mark -
#pragma mark View Life Cycle
- (void)viewDidLoad {
    [super viewDidLoad];
    
    // Initialize Fetch Request
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] initWithEntityName:@"TSPItem"];
    
    // Add Sort Descriptors
    [fetchRequest setSortDescriptors:@[[NSSortDescriptor sortDescriptorWithKey:@"createdAt" ascending:YES]]];
    
    // Initialize Fetched Results Controller
    self.fetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:self.managedObjectContext sectionNameKeyPath:nil cacheName:nil];
    
    
    // Configure Fetched Results Controller
    [self.fetchedResultsController setDelegate:self];
    
    // Perform Fetch
    NSError *error = nil;
    [self.fetchedResultsController performFetch:&error];
    
    if (error) {
        NSLog(@"Unable to perform fetch.");
        NSLog(@"%@, %@", error, error.localizedDescription);
    }
}


- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    if ([segue.identifier isEqualToString:@"addToDoViewController"]) {
        // Obtain Reference to View Controller
        UINavigationController *nc = (UINavigationController *)[segue destinationViewController];
        TSPAddToDoViewController *vc = (TSPAddToDoViewController *)[nc topViewController];
        
        // Configure View Controller
        [vc setManagedObjectContext:self.managedObjectContext];
        
    } else if ([segue.identifier isEqualToString:@"updateToDoViewController"]) {
        // Obtain Reference to View Controller
        TSPUpdateToDoViewController *vc = (TSPUpdateToDoViewController *)[segue destinationViewController];
        
        // Configure View Controller
        [vc setManagedObjectContext:self.managedObjectContext];
        
        if (self.selection) {
            // Fetch Record
            NSManagedObject *record = [self.fetchedResultsController objectAtIndexPath:self.selection];
            
            if (record) {
                [vc setRecord:record];
            }
            
            // Reset Selection
            [self setSelection:nil];
        }
    }
}


#pragma mark -
#pragma mark Fetched Results Controller Delegate Methods
- (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 {
    switch (type) {
        case NSFetchedResultsChangeInsert: {
            [self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;
        }
        case NSFetchedResultsChangeDelete: {
            [self.tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;
        }
        case NSFetchedResultsChangeUpdate: {
            [self configureCell:(TSPToDoCell *)[self.tableView cellForRowAtIndexPath:indexPath] atIndexPath:indexPath];
            break;
        }
        case NSFetchedResultsChangeMove: {
            [self.tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
            [self.tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;
        }
    }
}


#pragma mark -
#pragma mark Table View Data Source Methods
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return [[self.fetchedResultsController sections] count];
}



- (void)configureCell:(TSPToDoCell *)cell atIndexPath:(NSIndexPath *)indexPath {
    // Fetch Record
    NSManagedObject *record = [self.fetchedResultsController objectAtIndexPath:indexPath];
    
    // Update Cell
    [cell.nameLabel setText:[record valueForKey:@"name"]];
    [cell.nameLabel2 setText:[record valueForKey:@"name2"]];
    [cell.doneButton setSelected:[[record valueForKey:@"done"] boolValue]];
    
    [cell setDidTapButtonBlock:^{
        BOOL isDone = [[record valueForKey:@"done"] boolValue];
        
        // Update Record
        [record setValue:@(!isDone) forKey:@"done"];
    }];
}



- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath {
    return YES;
}

- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath {
    return NO;
}

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
    if (editingStyle == UITableViewCellEditingStyleDelete) {
        NSManagedObject *record = [self.fetchedResultsController objectAtIndexPath:indexPath];
        
        if (record) {
            [self.fetchedResultsController.managedObjectContext deleteObject:record];
        }
    }
}

#pragma mark -
#pragma mark Table View Delegate Methods
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    [tableView deselectRowAtIndexPath:indexPath animated:YES];
    
    // Store Selection
    [self setSelection:indexPath];
    
    // Perform Segue
    [self performSegueWithIdentifier:@"updateToDoViewController" sender:self];
}



// NSArray Below============

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    NSArray *sections = [self.fetchedResultsController sections];
    id<NSFetchedResultsSectionInfo> sectionInfo = [sections objectAtIndex:section];
    
    return [sectionInfo numberOfObjects];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    TSPToDoCell *cell = (TSPToDoCell *)[tableView dequeueReusableCellWithIdentifier:@"ToDoCell" forIndexPath:indexPath];
    
    // Configure Table View Cell
    [self configureCell:cell atIndexPath:indexPath];
    
    return cell;
}


- (IBAction)Calculate:(id)sender {
    //---------------
    
    NSInteger Tempsum = [[_dataArray valueForKeyPath:@"@sum.name2"] integerValue];
    
    
    _TotalAnimals.text = [[NSString alloc] initWithFormat:@"%.1ld", (long)Tempsum];

    //--------------

}


/*
 //---------------
 NSInteger TempsumTotalAnimals = [[_charactersArray valueForKeyPath:@"@sum.passenger"] integerValue];
 
 _TotalAnimals.text = [[NSString alloc] initWithFormat:@"%.1ld", (long)TempsumTotalAnimals];
 //--------------
 */




@end