Why would self.tempIndexPath ever be nill when moving a view?

[fresh83]

Having trouble understanding what this piece of logic is for or what exactly it does/when it would be called:

 if (!self.tempIndexPath) {
            //Why would self.temp be !?


            UITableViewCell *nearstCell = nil;
            NSArray *visibleCells = self.tableView.visibleCells;
            if (visibleCells.count > 0) {
                for (int i = 0; i < visibleCells.count; i++) {
                    UITableViewCell *cell = visibleCells[i];
                    CGPoint cellCenter = [cell.superview convertPoint:cell.center toView:self.tableView];
                    CGFloat top = cellCenter.y - cell.frame.size.height/2.0;

                    //mvTop =220  
                    //topA=0
                    //topB=100
                    //topC=200
                    //topD=300
                    if (mvTop < top) {
                        nearstCell = cell;
                        break;
                    }
                }
                if (!nearstCell) {

                    NSMutableArray *daySectionArray=[self.sortedTasksArray objectAtIndex:0];

                    [daySectionArray addObject:theMovingView.userInfo[@"object"]];

                    [self.sortedTasksArray replaceObjectAtIndex:self.tempIndexPath.section withObject:daySectionArray];


                    NSIndexPath *upperIndexPath = [NSIndexPath indexPathForRow:[self.tableView numberOfRowsInSection:0] inSection:0];
                    self.tempIndexPath = upperIndexPath;
                    [self.tableView insertRowsAtIndexPaths:@[self.tempIndexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
                } else {
                    NSIndexPath *upperIndexPath = [self.tableView indexPathForCell:nearstCell];
                    [self.tableView beginUpdates];
                    id object = theMovingView.userInfo[@"object"];

                    NSMutableArray *daySectionArray=[self.sortedTasksArray objectAtIndex:upperIndexPath.section];

                    [daySectionArray insertObject:object atIndex:upperIndexPath.row - 1];
                    [self.sortedTasksArray replaceObjectAtIndex:upperIndexPath.section withObject:daySectionArray];

                    NSIndexPath *tempIP = [NSIndexPath indexPathForRow:upperIndexPath.row - 1 inSection:upperIndexPath.section];
                    self.tempIndexPath = tempIP;
                    [self.tableView insertRowsAtIndexPaths:@[tempIP] withRowAnimation:UITableViewRowAnimationAutomatic];
                    [self.tableView endUpdates];
                }
            } else {
                NSMutableArray *daySectionArray=[self.sortedTasksArray objectAtIndex:self.tempIndexPath.section];


                [daySectionArray addObject:theMovingView.userInfo[@"object"]];

                [self.sortedTasksArray replaceObjectAtIndex:self.tempIndexPath.section withObject:daySectionArray];


                NSIndexPath *upperIndexPath = [NSIndexPath indexPathForRow:0 inSection:0];
                self.tempIndexPath = upperIndexPath;
                [self.tableView insertRowsAtIndexPaths:@[self.tempIndexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
            }
        }

[WeeTom]

@fresh83 Sorry for this late reply.
self.tempIndexPath is used to show a shadow in the TableViewController. So that we can see the future location.
This can be nil, when the moving item is first moved to be in the new TableViewController.
And when it is nil, we start to find the nearest location inside the TableViewController.