Adding a cell in UITableView with animation - iphone

Question

I have a UITableView. I'm population it from a NSDictionary with arrays for each set of items on the table: labels, footers, Headers, UIViews, etc.
In section 0, I want a row #2 appear when a switch in row #1 is switched to on.
What I have done and it works is, in numberOfRowsInSection I added this code:
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
if (interruptor.isOn==NO && section==0) {
return [[[infoTableContentArray objectAtIndex: section] objectForKey:kLabelKey] count]-1;
}else{
return [[[infoTableContentArray objectAtIndex: section] objectForKey:kLabelKey] count];
}
}
and the action linked to the switch (interruptor) is:
-(IBAction)accioInterruptor:(id)sender{
[infoAndSettingsTable reloadData];
}
so when the switch is switched, the table reloads and the cell appears or disappears.
it actually works, but there is no animation, which makes it, mhh... well, you know.
I've tried to implement the reloadRowsAtIndexPaths:withRowAnimation, adding it to the code called by the switch:
-(IBAction)accioInterruptor:(id)sender{
[infoAndSettingsTable beginUpdates];
[infoAndSettingsTable reloadRowsAtIndexPaths:[[infoTableContentArray objectAtIndex: 0] objectForKey:kLabelKey] withRowAnimation:UITableViewRowAnimationBottom];
[infoAndSettingsTable endUpdates];
}
But, it dowsn't work. It crashed on the line [infoAndSettingsTable endsUpdates];
BTW, in all the cases the following:
[[infoTableContentArray objectAtIndex: 0]
is the array which contains the labels for that section.
Am I doing it right or I'm Epic-Failing alltogether?
Thanks in advance!

Answer 1

simple way to do this......
[self.tableView beginUpdates];
[self.tableView insertRowsAtIndexPaths:insertIndexPaths withRowAnimation:UITableViewRowAnimationFade];
[self.tableView deleteRowsAtIndexPaths:deleteIndexPaths withRowAnimation:UITableViewRowAnimationFade];
[self.tableView endUpdates];
insertIndexPaths is an array of NSIndexPaths to be inserted to your table.
deleteIndexPaths is a array of NSIndexPaths to be deleted from your table.
Example array format for index paths :
NSArray *insertIndexPaths = [[NSArray alloc] initWithObjects:
[NSIndexPath indexPathForRow:0 inSection:0],
[NSIndexPath indexPathForRow:1 inSection:0],
[NSIndexPath indexPathForRow:2 inSection:0],
nil];
got it from this question

Answer 2

the argument to reloadRowsAtIndexPaths: should be an array of NSIndexPath objects identifying the rows you want to reload, not the labels for that section. Also, looks like you want to reload a section so I would try the following:
-(IBAction)accioInterruptor:(id)sender {
[self reloadSections:[NSIndexSet indexSetWithIndex:0] withRowAnimation:UITableViewRowAnimationBottom];
}

Answer 3

Why don't you just use UITableView's insertRowsAtIndexPaths:withRowAnimation:? It has been built exactly for this purpose, the UITableView class reference has the exact description and usage examples.
Apart from being cleaner it is also more performant since you don't have to reload the entire table (only really matters if you have lots of cells in it though)