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ios - Assertion failure in UITableView configureCellForDisplay:forIndexPath:

I'm not sure where the error is here, having looked at other similar issues. I received an Assertion failure.

Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: UITableView dataSource must return a cell from tableView:cellForRowAtIndexPath:

I think it is something simple but hope someone can help.

Below is my code:

#import "StockMarketViewController.h"

@interface StockMarketViewController ()

@end


@implementation StockMarketViewController
@synthesize ShareNameText, ShareValueText, AmountText;
@synthesize shares, shareValues;


- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section;
{
    return [shares count];

}

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



    NSString *currentValue = [shareValues objectAtIndex:[indexPath row]];
    [[cell textLabel]setText:currentValue];
    return cell;

}
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1 Answer

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by (71.8m points)

you are never creating a cell, you just try to reuse a dequeued cell. but as you never created one, there is none.

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath;
{
    static NSString *cellIdentifier = @"cell";
    UITableViewCell * cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
    if (!cell) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellIdentifier];
    }

    NSString *currentValue = [shareValues objectAtIndex:[indexPath row]];
    [[cell textLabel]setText:currentValue];
    return cell;
}

or try (only iOS 6+)

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

    NSString *currentValue = [shareValues objectAtIndex:[indexPath row]];
    [[cell textLabel]setText:currentValue];
    return cell;
}

from UITableView.h

- (id)dequeueReusableCellWithIdentifier:(NSString *)identifier;  // Used by the delegate to acquire an already allocated cell, in lieu of allocating a new one.
- (id)dequeueReusableCellWithIdentifier:(NSString *)identifier 
                           forIndexPath:(NSIndexPath *)indexPath NS_AVAILABLE_IOS(6_0); // newer dequeue method guarantees a cell is returned and resized properly, assuming identifier is registered

-dequeueReusableCellWithIdentifier: will always need a check, if a cell was returned, while
-dequeueReusableCellWithIdentifier:forIndexPath: can instantiate new one.


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