Difference of 2 NSArray's for animated insert/delete in UITableView

Question

At some point in my Application, I have an NSArray whose contents change. Those contents are shown in a UITableView. I'm trying to find a way to find the diff between the contents of before and after of the NSArray so i can pass the correct indexPaths to insertRowsAtIndexPaths:withRowAnimation: and deleteRowsAtIndexPaths:withRowAnimation: in order to have the changes nicely animated. Any ideas?

thx

Answer 1

Here's is wat i tried and it seems to work, if anyone has anything better, i'd love to see it.

[self.tableView beginUpdates];

NSMutableArray* rowsToDelete = [NSMutableArray array];
NSMutableArray* rowsToInsert = [NSMutableArray array];

for ( NSInteger i = 0; i < oldEntries.count; i++ )
{
    FDEntry* entry = [oldEntries objectAtIndex:i];
    if ( ! [displayEntries containsObject:entry] )
        [rowsToDelete addObject: [NSIndexPath indexPathForRow:i inSection:0]];
}

for ( NSInteger i = 0; i < displayEntries.count; i++ )
{
    FDEntry* entry = [displayEntries objectAtIndex:i];
    if ( ! [oldEntries containsObject:entry] )
    [rowsToInsert addObject: [NSIndexPath indexPathForRow:i inSection:0]];
}

[self.tableView deleteRowsAtIndexPaths:rowsToDelete withRowAnimation:UITableViewRowAnimationFade];
[self.tableView insertRowsAtIndexPaths:rowsToInsert withRowAnimation:UITableViewRowAnimationRight];

[self.tableView endUpdates];