Loading the next page

- [Instructor] Okay, so,…we're going to use the table view itself…to tell us when we need to scroll…to the next page.…And the way that we're going to do that…is by implementing a new delegate method…in our UI table view data source delegate.…So we're going to implement…the function table view will display self row index path.…Now this is a nice method that will be called back…when the cell is about to be displayed,…so prior to becoming on screen.…

So what we need to do is, first,…calculate what our next page is going to be.…So let's go ahead and create…a nice little helper variable…that will tell us what our next page index is.…And this will be an integer,…and it will be calculated.…So, we get our next page by figuring out…what the last page is.…So if we have product pages,…and maybe we just want to get the last one,…and, because last again returns an optional value,…let's safely unwrap this with a guard clause.…

And if we don't have a last page,…let's just go ahead and return a zero…so that we load the first page again…