使用NSMutableArray将数据添加到tableView

Question

I'm having a problem adding an item to my tableView.

I used to initialize an empty tableView at the start of my App and get it filled with scanned items every time the tableView reappears and there is an item in my variable.

Initialization of the tableView:

NSMutableArray *array = [[NSMutableArray alloc] initWithObjects:nil];
self.listArray = array;

TableView Data Source:

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    // Return the number of sections.
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    // Return the number of rows in the section.
    return [self.listArray count];
}
- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section 
{
    if(section == 0)
        return @"Eingescannte Artikel:";
    else
        return nil;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"testCell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];


    // Configure the cell...
    NSUInteger row = [indexPath row];
    cell.textLabel.text = [listArray objectAtIndex:row];//[NSString stringWithFormat:@"Das ist Zeile %i", indexPath.row];
    return cell;
}

(Not the whole thing but the ones I changed)

As you may have seen I use an NSMutableArray to add items to my tableView.

So if an item ist scanned I'm adding it to my array like this:

[listArray insertObject:sharedGS.strEAN atIndex:0]; //using a shared Instance where I implemented my variable.

I also tried to use an variable to extend my Index every time a new Item is added, but it won't work both ways.

I'm quite new to programming so an not-too-hard-to-understand-answer would be quite nice ;)

If there's any information missing, feel free to ask.

/edit: Trying to specify my question: The data from the variable is written in a TableViewCell, but if I scan another one the other one is just being replaced. Not sure if it's a problem with my array or my tableView...

/edit No.2: Found out(thanks to fzwo) that my array isn't working correctly. It just doesn't grow by an addObject: or insertObject:atIndex: command. But I just don't get why... :( All I'm doing: [listArray addObject:sharedGS.strEAN]; not that much space for errors in one simple line. Maybe I'm just too stupid to recognize what I'm doing wrong:D

Answer 1

You state that your problem is "adding an item to my tableView" , since you are adding the object to your array i am guessing the problem is that you are not reloading the table or that it is missing the dataSource binding.

You have not actually asked any question (even if you added info to "specify your question") so a wild guess, after

[listArray insertObject:sharedGS.strEAN atIndex:0];

put

[yourTableView reloadData];

Are you intentionally adding new items to the top of the table ? otherwise you could do [listArray addObject:sharedGS.strEAN]; to add new items to the bottom

Otherwise it's worth noting that you are misusing dequeueReusableCellWithIdentifier, look at the example below for proper usage:

// Try to retrieve from the table view a now-unused cell with the given identifier
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:MyIdentifier];

// If no cell is available, create a new one using the given identifier
if (cell == nil) {
    cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:MyIdentifier] autorelease];
}