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So in order to also get

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local notifications on iOS,

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we need to ask the user for permission.

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And for this, we an use another package

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which we also install with expo install,

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and that's the expo-permissions package.

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The expo-permissions package, as the name implies,

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helps us manage permissions.

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It helps us request permissions, and work with permissions.

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So once this is installed,

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in App.js or in any other file

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where you want to get those permissions,

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but here we only have this one component,

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we simply import everything as permissions

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from expo-permissions, just like that.

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And with imported, we need to ask the user for permission

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to show notifications before we try doing that.

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Now, it depends on your application

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when you want to ask the user.

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Maybe you wanna ask when the app starts up,

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maybe a better point of time is better.

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After all, you wanna ask for permissions

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when it's very likely that the user

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gives you the permission, right?

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Now here we'll do it right when the app starts up,

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so I will actually import the useEffect hook from react

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so that we can run logic when this component mounts,

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simply by passing an empty dependencies array here.

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And in there I now wanna use this permissions object

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which we imported here, to first of all check

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the permission status.

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And thereafter, if we don't have permission, to ask for it.

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So therefore here, we can call getAsync

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to first of all check the current permission status.

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We now need to specify for which permission

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we wanna get that information,

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and we can therefore access Permissions.NOTIFICATIONS...

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Whoops, all caps, though.

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To check how the current permissions status is

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for notification permissions.

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On Android this will do nothing,

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on iOS it will find out whether we already are allowed

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to send permissions.

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Now, this is a async task,

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and therefore it gives us a promise.

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Hence, we can use then here to proceed.

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Now in here, we'll get the status of that permission.

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So we'll get the information whether we do have permission

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to send notifications or not.

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Now we can check which status we got.

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There are a couple of possible values here,

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but in the end we're interested in the granted status.

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If we got that granted status, we don't need to continue.

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But if we don't have the granted status yet,

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we wanna ask for permission,

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because we haven't been granted those permissions before.

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So now we can use the permissions object again,

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but this time we call askAsync.

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Before, we checked the status,

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now we're asking for a new permission

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because now we know that we don't yet have the permission

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which we need.

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So now here we again access Permissions.NOTIFICATIONS,

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and now this will ask for getting that permission.

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This will return a promise, so we can overall return it here

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to stay in this promise chain which we've started here.

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And therefore, now here, we can again use then.

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You could also use async await,

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but in useEffect you shouldn't make this function async,

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instead you would have to wrap this into a new function

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which you immediately execute, just as a side note.

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But here, I will use good old then catch,

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and we'll reach the function in this then block

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after askAsync finished.

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Now again, here we'll get the status.

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Because of course, just because we're asking

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does not mean that we're getting the permission.

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So the user might still deny the permission,

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and in this case there is nothing we can do.

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So now we wanna check this status

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and find out if it's still not granted.

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And if that is the case, then well, as I said,

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there's nothing we can do.

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So here we can just return.

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We might show a message to the user,

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we might an alert that we now can't send any notifications.

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But in the end, there is nothing we can do here.

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If the status is granted though, then we're good.

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Now either way, we can definitely schedule a notification,

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because the worst case scenario

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is that we don't have permissions

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and therefore nothing happens.

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But now that we're asking, the best case scenario

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is that we did get the permission

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and therefore this here will succeed.

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Now actually, I have to step in here.

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This code has an error.

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We don't get the status string like this here,

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instead we get the statusObj,

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which then has a status property.

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And the same is the case here.

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We just didn't get an error before,

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because even though our code technically didn't work,

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we did request their permission still.

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But now this properly checks whether we have the permission.

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And in addition, we also have to adjust it

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in one other place.

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Here, if we already did have the permission,

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we of course will get granted as a response here, hopefully.

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And we'll not ask again.

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That means that in the next then block,

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we have a problem though.

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Because there we now expect to get our statusObj,

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but since we didn't ask again because we didn't need to,

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we'll not get that object here.

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So, accessing status will fail and we'll think

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that we didn't get the permission, even though we have it.

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So here we should return statusObj in that first then block

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so that in the next then block it is available

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for the cases where we already had permission.

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This is a change you should implement

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to ensure that your application properly detects

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its notifications permission status

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and does not think it doesn't have permissions,

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when it actually has them.

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So let's now save this.

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And make sure to restart that on your iPhone simulator.

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And now, right at the start,

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I'm asked whether I wanna grant this permission,

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because of that code we just added.

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And if we now click allow here,

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and trigger the notification and close the application,

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let's see if that now works here on iOS.

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Let's wait for the 10 seconds to go by.

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And here's our first local notification sent by our app.

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And now we got that working on both iOS and Android.

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And just as on Android, if we click on a notification here,

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we can open our app.

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So that's working.

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Now, one thing that did not work or where nothing happened,

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was when the app is in the foreground.

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Now in some cases that is the behavior you want.

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In some cases, if the app is open,

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not showing the notification might be absolutely fine.

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But if I come back to the reminder app example,

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just because it's in the foreground

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might not mean that you don't want to let the user know

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that some task is due.

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So therefore, let me next show you

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how you can handle notifications

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if the app is in the foreground.