UITableView puts cell content on wrong rows after scroll - ios

Question

Although there are couple of posts in the site regarding UITableview cell repetition when scrolled, I could nt find the solution, perhaps because am pretty new to obj-c.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
NSString *cellIdentifier = [NSString stringWithFormat:#"cell%d",indexPath.row];
UILabel *firstlabel = nil;
UILabel *secondlabel = nil;
UILabel *thirdlabel = nil;
myTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:nil];
if(!cell) {
cell = [[myTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:nil];
}
if (noOfRows < [_eachrow count]-1) {
_eachcolumn = [_eachrow[noOfRows] componentsSeparatedByString:#"|"];
firstlabel = [[UILabel alloc] initWithFrame:CGRectMake(0.0, 0, 142.0,tableView.rowHeight)];
firstlabel.font = [UIFont fontWithName:#"Verdana" size:12];
firstlabel.text = _eachcolumn[0];
firstlabel.textAlignment = ALIGN_LEFT;
firstlabel.autoresizingMask = UIViewAutoresizingFlexibleRightMargin |
UIViewAutoresizingFlexibleHeight;
[cell.contentView addSubview:firstlabel];
secondlabel = [[UILabel alloc] initWithFrame:CGRectMake(142.0, 0, 50.0,tableView.rowHeight)];
secondlabel.font = [UIFont fontWithName:#"Verdana" size:12];
secondlabel.text = _eachcolumn[1];
secondlabel.autoresizingMask = UIViewAutoresizingFlexibleRightMargin |
UIViewAutoresizingFlexibleHeight;
[cell.contentView addSubview:secondlabel];
thirdlabel = [[UILabel alloc] initWithFrame:CGRectMake(192.0, 0, 60.0,tableView.rowHeight)];
thirdlabel.font = [UIFont fontWithName:#"Verdana" size:12];
thirdlabel.text = _eachcolumn[2];
thirdlabel.textAlignment = ALIGN_CENTER;
thirdlabel.autoresizingMask = UIViewAutoresizingFlexibleRightMargin |
UIViewAutoresizingFlexibleHeight;
[cell.contentView addSubview:thirdlabel];
noOfRows++;
return cell;
}
else return cell;
}
So, my problem is when I scroll up or down, the cells keep placed at wrong rows without a pattern. Please help me resolve this issue. Thanks in advance

Answer 1

The problem occurs because the cells are reusable and you need to override the values each time in cellForRow .
Try this instead:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
NSString *cellIdentifier = [NSString stringWithFormat:#"cell%d",indexPath.row];
myTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if(!cell) {
cell = [[myTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
UILabel *firstlabel = nil;
UILabel *secondlabel = nil;
UILabel *thirdlabel = nil;
_eachcolumn = [_eachrow[noOfRows] componentsSeparatedByString:#"|"];
firstlabel = [[UILabel alloc] initWithFrame:CGRectMake(0.0, 0, 142.0,tableView.rowHeight)];
firstlabel.font = [UIFont fontWithName:#"Verdana" size:12];
firstlabel.text = _eachcolumn[0];
firstlabel.textAlignment = ALIGN_LEFT;
firstlabel.autoresizingMask = UIViewAutoresizingFlexibleRightMargin |
UIViewAutoresizingFlexibleHeight;
firstlabel.tag = 10;
[cell.contentView addSubview:firstlabel];
secondlabel = [[UILabel alloc] initWithFrame:CGRectMake(142.0, 0, 50.0,tableView.rowHeight)];
secondlabel.font = [UIFont fontWithName:#"Verdana" size:12];
secondlabel.text = _eachcolumn[1];
secondlabel.autoresizingMask = UIViewAutoresizingFlexibleRightMargin |
UIViewAutoresizingFlexibleHeight;
secondlabel.tag = 20;
[cell.contentView addSubview:secondlabel];
thirdlabel = [[UILabel alloc] initWithFrame:CGRectMake(192.0, 0, 60.0,tableView.rowHeight)];
thirdlabel.font = [UIFont fontWithName:#"Verdana" size:12];
thirdlabel.text = _eachcolumn[2];
thirdlabel.textAlignment = ALIGN_CENTER;
thirdlabel.autoresizingMask = UIViewAutoresizingFlexibleRightMargin |
UIViewAutoresizingFlexibleHeight;
thirdlabel.tag = 30;
[cell.contentView addSubview:thirdlabel];
return cell;
}
else
{
((UILabel *)[cell.contentView viewWithTag:10]).text = _eachcolumn[1];
((UILabel *)[cell.contentView viewWithTag:20]).text = _eachcolumn[2];
((UILabel *)[cell.contentView viewWithTag:30]).text = _eachcolumn[3];
return cell;
}
}