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So did you manage to complete the challenge?
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I really hope that you gave it a good go because it is a really, really good challenge to understand
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these complex and rather abstract concepts.
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And I imagine that if you played around with it quite a bit,
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fix some bugs, and figure out how to make it work inside the TodoListViewController,
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then you've got a good grasp of how these-- of how superclasses, subclasses, and all of this works.
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So spoiler alert, I'm going to show you the solution now.
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So if you haven't tried it,
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then go back and do it now.
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All right.
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So the first thing that we need do inside TodoListViewController, just as we did inside the 
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CategoryViewController is to change the inheritance. Instead of subclassing 
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UITableViewController, Apple's component,
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we're going to subclass SwipeTableViewController.
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And if you think about it, the UITableViewController is almost like the grandad of TodoListViewController
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now. Because inside SwipeTableViewController, it now inherits TableViewController.
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So, say, if this was granddaddy, then this is going to be your dad, and this is going to be you.
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Now, if it's a little bit upsetting to think of yourself as a block of code, then I apologize for that,
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but I think it's a good analogy.
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So the next thing that we need to do is to change our cellForRowAt an indexPath method because we're no
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longer going to be dequeuing our cell inside here,
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instead we're going to be using the superclass' cell.
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So we're gonna say let's cell = super, which you can see is the SwipeTableViewController,
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.tableView, cell for indexPath.
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So, now that we have this reference to the cell that is from the method inside our super view controller
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so inside here, and that cell is already set up as a SwipeTableViewCell and the cell's delegate is
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self.
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Now, it might be worth just going back and making sure that table view cell is set as a 
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SwipeTableViewCell,
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and it uses the SwipeCellKit module.
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We did that for the first cell in the tutorial and this might be something that you would have overlooked.
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So once that's done, then we've got this reference to the cell from our superclass.
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And we're going to set the cell's textLabel,
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we're going to set the cell's accessoryType, and then we're going to return the cell. And we don't have
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to deal with any of the SwipeCellKit over here.
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Now, the next thing to add in is that we will need to override that function that we've got inside
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SwipeTableViewCell which is the updateModel(at: indexPath).
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So we're going to go over here. We're going to override updateModel(at: indexPath) and we're going to
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take that indexPath to delete our data. So we can say if let item = todoItems? which is an
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optional, so we'll use optional chaining to grab a hold of the item at indexPath.row,
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and this is the indexPath that gets passed in through our superclass method updateModel an indexPath
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which gets triggered, if you remember, when the user swipes on a particular cell to try and delete it.
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So we're going to grab a reference to our item at this particular index. And if this is not nil, then
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we are going to use our realm.write method to make some changes inside our Realm. And the changes that we
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want to make are realm.delete. And the object that we want to delete is this item Object.
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Now, as Xcode is helpfully telling us realm.write can throw,
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so we have to mark it with a try,
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and therefore, we're going to put it inside a do-catch block.
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And now we're ready to run our app.
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So if we go inside home, you can see that we've got three items, and we can still check them off as we
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did before using our didSelectRowAt indexPath delegate method.
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But now we have the special power of swiping and getting that Delete show up,
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and if we click on it or swipe all the way, then it deletes it from our list of items.
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Now, what if we wanted our items to have the same height as the ones inside our categories?
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Now, we can either copy this rowHeight over to our TodoListViewController. But if we're going to have
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it the same for both and we're inheriting from swipe view table view controller, then it makes
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more sense for it to go over here. And now, if we hit run, you'll see that we get that nice expanded height
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in both view controllers.
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So, all right, how did that go?
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Did you manage to get in?
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If not, make sure that you have a look at the previous lesson as well as this one, and try and go and
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attempt it again.
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It's really, really important that at this stage, that you really try things yourself. And, you know, you
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will fail, and you will fall over, and you will have to struggle a lot,
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but believe me, the more that you struggle, the more that you learn.
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So that's all for this lesson.
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And in the next lesson, we're going to improve the appearance of our app even further by adding gradients
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to our cells.
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So for all of that and more, I'll see you on the next lesson.