ios - Accessing custom cell attributes outside of cellForRowAtIndexPath

Question

I want some thing like image below. User can click on + or - button and the increased or decreased count is display in UILabel i.e 1 in the image below.
I know how to implement custom table view cell .I know how to implement the selector too. but I need to set the label text according as the button clicked thats only is the problem . How can I update button clicked and set text of UILabel of custom cell outside from cellForRowAtIndexPathwith add subtract features.

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

    //self.tableView.separatorStyle = UITableViewCellSeparatorStyleNone;

     static NSString *simpleTableIdentifier = @"ProductListVIICell";

     ProductListVIICell *cell = (ProductListVIICell *)[tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];

    if (cell == nil)
    {
         NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"ProductListVIICell" owner:self options:nil];
         cell = [nib objectAtIndex:0];
     } ....................................
        cell.btnMinus.tag = indexPath.row;
        cell.btnPlus.tag = indexPath.row;

        [cell.btnPlus addTarget:self action:@selector(addItem:) forControlEvents:UIControlEventTouchUpInside];
        [cell.btnMinus addTarget:self action:@selector(deleteItem:) forControlEvents:UIControlEventTouchUpInside];

        cell.lblCount.tag = [[NSString stringWithFormat:@"%d%d",addBtnClickCount,addBtnClickCount] integerValue];


        return cell;
    }

I need to do things here but didnt get what I want to acheive. cell.lblTitle.text isnt working

  #pragma mark - UIButton selector

-(void)addItem:(UIButton*)button {
    itemCount++;
    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:button.tag inSection:1];
    ProductListVIICell *cell = (ProductListVIICell *)[self.tableView cellForRowAtIndexPath:indexPath];
      cell.lblCount.textColor = [UIColor redColor];
     cell.lblTitle.text = [NSString stringWithFormat:@"%d",itemCount];

    NSIndexPath* rowToReload = [NSIndexPath indexPathForRow:[button tag] inSection:0];
    NSArray* rowsToReload = [NSArray arrayWithObjects:rowToReload, nil];
    [self.tableView reloadRowsAtIndexPaths:rowsToReload withRowAnimation:UITableViewRowAnimationNone];
     NSLog(@"%d",itemCount);
    [self.tableView reloadData];


}

-(void)deleteItem:(UIButton*)button {
    itemCount--;
     NSIndexPath *indexPath = [NSIndexPath indexPathForRow:button.tag inSection:1];
    ProductListVIICell *cell = (ProductListVIICell *)[self.tableView cellForRowAtIndexPath:indexPath];

    cell.lblCount.textColor = [UIColor redColor];
    cell.lblTitle.text = [NSString stringWithFormat:@"%d",itemCount];

    NSIndexPath* rowToReload = [NSIndexPath indexPathForRow:[button tag] inSection:0];
    NSArray* rowsToReload = [NSArray arrayWithObjects:rowToReload, nil];
    [self.tableView reloadRowsAtIndexPaths:rowsToReload withRowAnimation:UITableViewRowAnimationNone];
     NSLog(@"%d",itemCount);
    [self.tableView reloadData];

}

These links are useful too

Accessing cell attributes outside of cellForRowAtIndexPath

http://code.tutsplus.com/tutorials/blocks-and-table-view-cells-on-ios--mobile-22982 but it is only for UITableViewCell not the custom cell

I was able to solve my problem using following

@interface ProductListVC ()
{
    int count;
    bool addBtnClicked;
    bool minusBtnClicked;


}

@property (strong,nonatomic) NSMutableArray* quantityArray; //stores label
@property (strong,nonatomic) NSMutableArray* quantityLabelArray; //stores label

- (void)viewDidLoad {

    [super viewDidLoad];

    _quantityLabelArray = [[NSMutableArray alloc] init];
     _quantityArray = [[NSMutableArray alloc] init];

//determine num of row prevent index 2 beyond bounds for empty array error i.e insert straight to let's say index 3
    for (int i=0; i <=[_productArray count]; i++) {
            [_quantityArray addObject:@"0"];

        }
}


- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
................

if (!_quantityArray || !_quantityArray.count){
        cell.lblCount.text = [NSString stringWithFormat:@"%d", 0];

    }else{
        cell.lblCount.text = [_quantityArray objectAtIndex:indexPath.row];
     }
     [_quantityLabelArray addObject:cell.lblCount];


    if (addBtnClicked || minusBtnClicked) {
        //If add or minu button is reloading the cell

        cell.lblCount.text = [_quantityArray objectAtIndex:indexPath.row];
        //NSLog(@"%@",cell.lblCount.text);
        [_quantityLabelArray replaceObjectAtIndex:indexPath.row withObject:cell.lblCount];
        addBtnClicked = NO;
        minusBtnClicked = NO;

    }
    else
    {

    }

    cell.btnMinus.tag = indexPath.row;
    cell.btnPlus.tag = indexPath.row;
    cell.lblCount.tag = indexPath.row;

    [cell.btnPlus addTarget:self action:@selector(addItem:) forControlEvents:UIControlEventTouchUpInside];
    [cell.btnMinus addTarget:self action:@selector(deleteItem:) forControlEvents:UIControlEventTouchUpInside];

    cell.selectionStyle = UITableViewCellSelectionStyleNone;
    return cell;
}



#pragma mark - UIButton selector

-(void)addItem:(UIButton*)button

{

     NSLog(@"btn tag %ld",(long)[button tag]);
     NSLog(@"quantitylblarry %@",_quantityLabelArray);

        UILabel* lblShowCount = [_quantityLabelArray objectAtIndex:[button tag]];
        if ([lblShowCount.text integerValue]< 10) {
            count = count+1;
            lblShowCount.text = [NSString stringWithFormat:@"%ld", [lblShowCount.text integerValue]+1];
        }

     NSLog(@"quantity array count %lu",(unsigned long)_quantityArray.count);

        if (_quantityArray.count > [button tag] ) {

            [_quantityArray removeObjectAtIndex:[button tag]];
            [_quantityArray insertObject:lblShowCount.text atIndex:[button tag]];
        }

        else{

            [_quantityArray insertObject:lblShowCount.text atIndex:[button tag]];
        }
        addBtnClicked = YES;

        NSLog(@"quantity array %@",_quantityArray);
        NSIndexPath* rowToReload = [NSIndexPath indexPathForRow:[button tag] inSection:0];
        NSArray* rowsToReload = [NSArray arrayWithObjects:rowToReload, nil];
        [self.tableView reloadRowsAtIndexPaths:rowsToReload withRowAnimation:UITableViewRowAnimationNone];

    }





-(void)deleteItem:(UIButton*)button{

     NSLog(@"%ld",(long)[button tag]);
    UILabel* lblShowCount = [_quantityLabelArray objectAtIndex:[button tag]];


        if ([lblShowCount.text integerValue]>=1) {
            count = count-1;
            lblShowCount.text = [NSString stringWithFormat:@"%ld", [lblShowCount.text integerValue]-1];

        }

        NSLog(@"%lu",(unsigned long)_quantityArray.count);

        if (_quantityArray.count > [button tag] ) {
            [_quantityArray removeObjectAtIndex:[button tag]];
            [_quantityArray insertObject:lblShowCount.text atIndex:[button tag]];
        }
        else{
            [_quantityArray insertObject:lblShowCount.text atIndex:[button tag]];

        }
        NSLog(@"%@",_quantityArray);
        minusBtnClicked =YES;

        NSLog(@"quantity array %@",_quantityArray);
        NSIndexPath* rowToReload = [NSIndexPath indexPathForRow:[button tag] inSection:0];
        NSArray* rowsToReload = [NSArray arrayWithObjects:rowToReload, nil];
        [self.tableView reloadRowsAtIndexPaths:rowsToReload withRowAnimation:UITableViewRowAnimationNone];

 }

Answer 1

it is better to use custom cell. Check this tutorials or this one, then you will need to add delegate to this cell so that you can sync quantities with you ViewController

i.e.

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    CustomTableViewCell *cell = (CustomTableViewCell *)[tableView dequeueReusableCellWithIdentifier:@"CustomTableViewCell" forIndexPath:indexPath];
    cell.delegate = self;
    cell.itemIndex = indexPath.row;
    ....
    return cell
}

UPDATE

if you have a custom cell, you would add an UILabel outlet and modify its text in the action of +/- buttons, all this code will be in CustomTableViewCell.m

-(void)addItem:(UIButton*)button {    
    self.itemQuantity++; 
    [self updateQuantity];
}

-(void)deleteItem:(UIButton*)button {
    self.itemQuantity--;
    [self updateQuantity];
}
- (void)updateQuantity{
    self.lblCount.text = [NSStirng stringWithFormat:@"%d", self.itemQuantity];
    [self.delegate updateItemAtIndex:self.itemIndex withQuantity:self.itemQuantity];
}

UPDATE: COMPLETE SOLUTION

1. Model

@interface Item : NSObject
@property (nonatomic, strong) NSString *title;
@property (nonatomic) NSInteger quantity;
@end

@implementation Item

@end

2. Custom Cell

@interface CustomItemTableViewCell : UITableViewCell

@property (nonatomic, weak) IBOutlet UILabel *lblTitle;
@property (nonatomic, weak) IBOutlet UILabel *lblCount;
@property (nonatomic, assign) Item *item;
@end

@implementation CustomItemTableViewCell

- (void)updateCellWithItem:(Item *)item {
    self.item = item;
    [self updateCellView];
}
- (void)updateCellView {
    self.lblTitle.text = self.item.title;
    self.lblTitle.text = [NSString stringWithFormat:@"%ld", self.item.quantity];
}
- (IBAction)addItem:(UIButton*)button {
    self.item.quantity++;
    [self updateCellView];
}

- (IBAction)deleteItem:(UIButton*)button {
    self.item.quantity--;
    [self updateCellView];
}

@end

3. TableViewController

@interface ItemsTableViewController : UITableViewController
@property (nonatomic, strong) NSArray *items;
@end

@implementation ItemsTableViewController

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    return self.items.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    CustomItemTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"CustomItemCell" forIndexPath:indexPath];

    [cell updateCellWithItem:self.items[indexPath.row]];

    return cell;
}