[MUSIC] Okay, I have the Apple TV simulator interface up and running here. The simulator is pretty bare bones. It really just comes with the Settings app. You can see the little sample app, or the quick single image app that we started out with in the last video there. And I've also added one more, I've compiled and installed Apple's UIKit Catalog app. Now, that's a sample code that's available from their developer website, and you might want to check that out too. So normally a user would have actually many rows of apps. We just have one row of apps here. Now I can't just click on an app or tap on an app, obviously. [LAUGH] It's a TV right? You wouldn't want to be running up to your TV and tapping on the the screen. Users are going to be swiping right, left, up, and down on a remote to move a focus around. On the Mac I can just use the arrow keys, so I can just use the arrow keys to kind of jump back and forth between these icons. When an item is focused, you can see it jumps a little bit out on the screen, and I can perform actions on focused items. For example, if I press the Enter key, it simulates what the user would be doing when they're clicking the remote. So if do that on an app, it launches the app. And then if I press Esc, it simulates pressing the Menu key on the app, which always goes back up one level, and eventually gets you back to the home screen. So I'll just press Enter again, and go back into this Catalog app. So this is the UIKit Catalog app, and its root U controller, the one that we're really looking at here, is actually a tab view controller. And it's the same class as the tab view controller used on the iPhone. So if you know how to set up the iPhone's tab view controller, you can set up a controller similar to this one on the Apple TV. And then again, I can navigate around using the arrow keys. And UIKit for TV OS actually knows what to focus on by searching in the direction that I'm typing on the keyboard. So I'm typing up and down here, go back up, get back to that tab view and I can go across. Okay, so I'm just going to go down into here, and we'll take a look at this Collection View Controller. It's essentially really the same class and API as the iOS version of Collection View. The important difference here is how scrolling works. In iOS, what I would do when I'm swiping through a scroll view, I actually swipe the content and the direction when I want it to move. It's like I'm directly manipulating the content. But in TV OS I'm actually moving the focus, right? The content scrolls into view so that I can see what I've actually focused on. So it's kind of like more having an invisible cursor that snaps between objects on the screen. But you're using your remote to move between objects instead of directly manipulating them. After developing for a touch interface for iPhones and iPads and other devices, it actually kind of is a little bit of an adjustment to start thinking like this. Anyway, let's go back out of this screen. Again, I press the Menu button on the remote or press Esc on the Mac keyboard to go back up a level. And you'll notice that on the screen there is no back button, right? There's no need to take up space on the screen since that Menu button is available on the remote. Okay, in the next video we'll look at how to customize a Collection View so that it highlights a user, just like we're seeing with this when they have it focused. So it gives those nice growing and focused animations there.
