Deleting and adding rows in uitableview [closed] - objective-c

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Closed 10 years ago.
guys, I have tableview, which is loading from my nsarray, but after managing cells, it shows elements in incorrect places.
Generating cell:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSArray *currentArray = [comments objectAtIndex:indexPath.section];
NSDictionary *currentComment = (NSDictionary *)[currentArray objectAtIndex:indexPath.row];
static NSString *CellIdentifier = #"TitleCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];
}
int commentLevel = [[currentComment objectForKey:#"level"] intValue];
NSString *commentText = [currentComment objectForKey:#"text"];
cell.textLabel.tag = 0xff ;
cell.textLabel.numberOfLines = 0;
cell.textLabel.font = [UIFont fontWithName:#"Verdana" size:17.0];
cell.textLabel.lineBreakMode = UILineBreakModeWordWrap;
cell.textLabel.text = commentText;
cell.textLabel.backgroundColor = [UIColor clearColor];
if (commentLevel > 0 && cell.imageView.image == nil) {
cell.imageView.image = [UIImage imageNamed:#"06-arrow-northwest.png"];
}
if (commentLevel == 0 && [[openedSections objectAtIndex:indexPath.section] boolValue] == NO) {
if ([currentArray count] > 1) {
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
}
}
return cell;
}
Editing method:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
[tableView deselectRowAtIndexPath:indexPath animated:YES];
if ([[openedSections objectAtIndex:indexPath.section] boolValue] == NO) {
[openedSections replaceObjectAtIndex:indexPath.section withObject:[NSNumber numberWithInt:1]];
NSMutableArray *rows = [[NSMutableArray alloc] init];
int i = 1;
while (i < [[comments objectAtIndex:indexPath.section] count]) {
NSIndexPath *path = [NSIndexPath indexPathForRow:i inSection:indexPath.section];
[rows addObject:[path copy]];
[path release];
i = i + 1;
}
[tableView beginUpdates];
[tableView insertRowsAtIndexPaths:rows withRowAnimation:UITableViewRowAnimationAutomatic];
[tableView endUpdates];
[rows release];
} else if (indexPath.row == 0) {
[openedSections replaceObjectAtIndex:indexPath.section withObject:[NSNumber numberWithInt:0]];
NSMutableArray *rows = [[NSMutableArray alloc] init];
int i = 1;
while (i < [[comments objectAtIndex:indexPath.section] count]) {
NSIndexPath *path = [NSIndexPath indexPathForRow:i inSection:indexPath.section];
[rows addObject:[path copy]];
[path release];
i = i + 1;
}
[tableView beginUpdates];
[tableView deleteRowsAtIndexPaths:rows withRowAnimation:UITableViewRowAnimationAutomatic];
[tableView endUpdates];
[rows release];
}
}
Have you any ideas?

Answer 1

You need to update your NSArray whenever you modify the cells in your table, otherwise your data source and view will get out of sync.
So whenever you call:
[tableView insertRowsAtIndexPaths:rows withRowAnimation:UITableViewRowAnimationAutomatic];
You should put
for (NSIndexPath *indexPath in rows)
{
[self.myDataArray insertObject:myRowModel atIndex:indexPath.row];
}
As well so that your view and model stay in sync.
Obviously the above is pseudocode (you'd have to create an instance of whatever your model objects are), and your array will have to be an NSMutableArray or it will crash when you try to insert into it.