Back in Xcode within our ViewController here is where we're going to configure

a local notification.

So we'll create a function called scheduleNotification,

which we will call from our viewDidLoad methods.

And then let's implement the scheduleNotification.

We're going to delete that did receive memory warning.

We don't need that template method.

If you recall from the slides, we need three objects to create a notification.

The first being the content.

Let's create our content object first.

We will use the class name UNMutableNotificationContent.

So the same let content =

UNMutableNotificationContent and

as you can see I don't have autocomplete because I forgot to import

the UserNotification module.

Okay, if we command click on this class,

we can look at its definition and see what all do we have available.

So we have the badge, we have a body, we have

an image, we have sound, we have subtitle and we have title.

So let's start with the basics.

Let's start with the title, subtitle, and body.

So it's a content.title = 10

second notification demo and

then content.subtitle = From Treehouse and

finally, content.body = Notification

after 10 seconds- Your alert is ready!

Now that we have our content,

we need a way to trigger our notification.

We will use a time based trigger.

Remember we have either time based, calendar based, or

location based triggers.

So for this example, we're going to use the time base trigger.

So let say let trigger = UNTimeIntervalNotificationTrigger.

And this takes in two parameters.

The time in seconds.

So as you guessed from the title and

the body this is going to be a 10 second trigger notification.

And whether it repeats or not will say false because we don't want this

notification to keep repeating every 10 seconds.

That would be highly annoying.

So finally we need to create a request.

The request composes a notification request object which can then be

added to the system's default notification center of the notification queue.

So let's say, let request = UNNotificationRequest,

which takes in three parameters.

Now the first parameter is an identifier for our notification.

You see this goes into a notification queue.

And if we wanted to later retrieve that from the queue before it has been

triggered we can retrieve it and either delete it or update it.

So it's important that we give it a unique identifier.

I'll just call this 10.second.notification.

And the content is our content object and the trigger is our trigger.

And finally we will add request to our current notification center.

So as we had done in our app delegate we will access the current

notification center and then we can simply add to it.

So we add with two parameters,our request

and we can specify completion handler or

we can simply say no if you don't want a completion handler.

So that's it.

We have created the content trigger in requests and then we have added

that request to our default or current notification center and this should

be enough to schedule a notification which will display an alert in 10 seconds.

So let's go in and run our application.

So will first let our app launch in the simulator and

then will click on hardware and home so

that we can see the notification alert and there it is.

It say's Ten second notification demo from tree house.

So congratulations we've generated our first notification.

Next let's add our badge app icon when this notification is fired.

Oftentimes you want to grab a user's attention by displaying a badge app icon.

For example the number of unread emails or messages.

So going back to our code within our content.

So as you must have noticed that the content object has a badge property,

which we're going to set to 1.

Course you can assign any number to it, but we're going to assign it a 1.

And then run our application in the simulator.

And as soon as our notification is displayed, you will notice that a badge

with the number one is displayed on top of our app icon.

And here you go as you can see that red one or

that one with the circular red on top of the app icon.

So great. This is how you badge an app icon.

So next we're going to set the sound property on our content object.

So if we want to have a standard sound,

we can simply do a content.sound = UNNotification.

NotificationSound.default().

So this is going to be a default system sound for our notification.

But if you want something custom, we can do that as well.

So in our case, we're gonna add a custom sound.

So for that, I need to add this file to our project first.

So I'm gonna drag this gong.aif, aif stands for audio interchange format.

So make sure that it's selected copy items if needed and add to targets.

So I'm gonna select the target here which is the NotificationsDemo and

then hit Finish.

So instead of using the default sound, we're going to give it a name of a file.

So in our case it's called gong.aif.

So now when our application runs, and our notification is displayed,

it's going to have this nice little gong sound upon displaying.

I'll notice that the badge does not disappear.

There's that beautiful gong sound.

And notice that the badge does not disappear from previously if you want

the badge to disappear, then we would have to set it to 0 and

that will make the badge disappear.

Though you can updated to a different number.

I'm just gonna set it back to 1.

So finally we can now create rich notifications by displaying either video,

images or audio within them.

So let's add an image to our notification.

So I'm gonna drag this image to our project first.

Once again, make sure that the copy items if needed is checked, and

your target is checked, and then hit finish.

So first we need the URL to that image within our application bundle.

So I'm gonna say let imageURL = Bundle.main.url and

we're going to select forResource withExtension.

So this is treehouse and the extension here is jpg.

So from there we need to create an attachment object using

the UNNotification attachment class.

So I'll say let the attachment

equal UNNotification.

And here is the designated initializer.

So the first is the identifier of the attachment next is a URL and

then finally you have options.

So the identifier we'll simply just called this treehouse.jpg.

The URL is the imageURL.

And options, we're just going to specify nil.

But if we look at the definition for this method,

so the compiler is complaining here.

And I think we just need an exclamation to implicitly unwrap this imageURL optional.

We have yet another error.

So that's not the error which the other it says can call throw right.

So this notification attachment throws in error.

And we are not catching it or you're not even specifying a try.

So we just put a try bang over there.

And now we have an attachment object.

So what I wanted to show you as if you option click,

you will get all the options.

So it says Attachment Attributes.

You can see that in the documentation and you have different kinds of attributes.

Like one of the things is how do you want your image thumbnail to be clipped?

You can specify the clipping record over here or

if you want the thumbnail to be hidden or if you want HindKey.

So all of these options you can specify.

So finally, we need to attach this to our content.

So we'll say content.attachments = [attachment].

So you can have multiple attachments and

in our case we simply have this one attachment.

Okay, let's run our application and see how it displays the image.

Command shift H to go home and our alert will soon be displayed.

There it is.

And if you pull down on this alert,

what it does it shows you an expanded view of what the image looks like.

So the user can do that if they're curious to see what the image looks like.

All right, and

then we can just swipe up or just hit on this x to get rid off the alert.

So we've covered all the basics of creating the content for a notification.

So you've seen how you can create a basic notification with titles,

subtitle and body.

Then you saw that you can add a badge to the app icon.

You can add custom sounds are used default system sounds.

And finally we added an attachment in our case we added an image attachment but

similarly you can add a video or audio attachment if you wanted to.

So next stop, what happens once the user receives the notification and taps on it.