Question

So, there is a problem: when i checking a cell in table, another cell checked also, but i want only one checking at time. There is source:

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

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault 
                                       reuseIdentifier:CellIdentifier] autorelease];
    }

    cell.textLabel.text = [[self.symptoms objectAtIndex:indexPath.row ] objectForKey:@"name"];


    return cell;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {


    NSLog(indexPath);
    UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];

    if (cell.accessoryType == UITableViewCellAccessoryCheckmark) {
        cell.accessoryType = UITableViewCellAccessoryNone;

    } else {
        cell.accessoryType = UITableViewCellAccessoryCheckmark;
    }

    [tableView deselectRowAtIndexPath:indexPath animated:YES];
}

Answer 1

Try to not reuse the cell.
Because when you reuse the cell you also reuse the checkmark-/accessory-state.
So why not removing the cell queuing.

You can try:

.h file:

@property (nonatomic, retain) NSMutableDictrionary *checkedState;

.m file:
(at top)

@synthesize checkedState = checkedState_;

(rest)

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

    UITableViewCell *cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault 
                                       reuseIdentifier:nil] autorelease];

    cell.textLabel.text = [[self.symptoms objectAtIndex:indexPath.row ] objectForKey:@"name"];

    if(self.checkedState) {
      NSNumber *checkmarkStateNumber = [self.checkedState objectForKey:[NSNumber numberWithInt:indexPath.row]];
      if(checkmarkStateNumber && [checkmarkStateNumber boolValue] == YES) {
        cell.accessoryType = UITableViewCellAccessoryCheckmark;
      }

    return cell;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {


    NSLog(indexPath);
    UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];

    if(!checkedState) { self.checkedState = [NSMutableDictionary dictionary]; }


    BOOL checkmarkState = NO;
    if (cell.accessoryType == UITableViewCellAccessoryCheckmark) {
        cell.accessoryType = UITableViewCellAccessoryNone;

    } else {
        cell.accessoryType = UITableViewCellAccessoryCheckmark;
        checkmarkState = YES;
    }

    [self.checkedState setObject:[NSNumber numberWithBool:checkmarkState] forKey:[NSNumber numberWithInt:indexPath.row]];

    [tableView deselectRowAtIndexPath:indexPath animated:YES];
}

Update 1:
Now it should also store the checkmark state!