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Alright, so we're now ready to run the

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app again, to see how it behaves. We're

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going to do that, then talk about what's

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wrong with the code. So we need to see,

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firstly, how the app behaves some scratch.

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So I'm going to go back to our emulator,

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and I'm going to delete this app so

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we're starting from a clean slate. So I'm

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going to install that, and I'll run it

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again, and we'll open our logcat so that

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we can see what's going on. So the first

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test that we want to do here, is to see

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how it behaves when we deny access. I'm just

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gonna move this over a little bit more,

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so we can see a bit more of the log.

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Alright, so as I said, the first test is

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going to be to see how it behaves when

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we deny access. So I'm gonna click on

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Deny, and now when I click on the FAB, it

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should display our Snackbar and the link

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there to Grant Access, which it is. And

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that should continue to appear whenever

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we click the FAB. So if I swipe that off

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screen - the Snackbar. Click it again - it

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comes back again, which is good and which is

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the expected behavior. And in the logcat,

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you can see as I'm doing that,  the FAB's

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onClick method starting and ending.

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Alright, so let's see now what happens

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when the Grant Access link is clicked. So

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the logcat now, you can see, has the

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onClick method starting again - this time

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a call to requestPermissions, and then

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the onClick method ending. And as a

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result, we've now got the Android dialogue

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asking for permission to access the

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contacts. So when I come over here and

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click on Deny again, we see permission

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refused over here, in the log.

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We're now onRequestPermissionsResult:

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callback is called. So let's do that

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again,

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but this time, when I click on Grant

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Access, I'm going to check the Don't ask

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again checkbox and click on Deny. So now

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effectively, what I've done, is told

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Android not to ask again. So in terms

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of our code, the call to shouldShowRequest

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PermissionRationale should now return

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false. So in other words, this bit of

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code down here should now be

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executed.

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So let's actually check that. I'm going

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to click on the FAB button again,

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click on Grant Access, and you can see

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what's happened in this case - that code

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was executed, and the settings for the

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application is now showing on the screen

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again. so that bit's working well, and

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looking at the logcat down here as well,

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you can see the URI showing on the

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screen there; package:academy.learn

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programming.contentproviderexample. So

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it's that URI, together with the ACTION

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_APPLICATION_

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DETAILS_SETTING - a value that

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we used in setAction - that sets, or let's

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rather, Android open the settings for

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this app, rather than just going into the

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main settings screen. And notice down here

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also, in the log, that the Snackbar's

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onClick method has finished. So you can

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see the Snackbar onClick: ends entry

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after the launching of the settings, and

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we'll see why that's important in a

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moment. Alright, so back over in our app,

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I'm going to click on Permissions, and

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then I'm going to grant access to our

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Contacts, by turning that on. Once I've

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done that, tapping back a few times

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should take us back to our app, which it's

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done here now. But notice that when I'm

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doing that, nothing's appeared over here

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in the logcat. The app now has the

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permission it needs, but it doesn't know

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that it has got that permission. So you

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can see, basically at this point, where

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I've tapped the FAB again, the Snackbar

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still appearing instead of our contact

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details. Now if I quit the app, close this

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down, and run it again and

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click on our button - our FAB - it is actually

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working correctly. And you can see, in

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fact, the permission's granted now

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showing in our logcat. But really,

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that's not the best user experience

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requiring the user to shut down the app

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and start it up again, in order to

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proceed.

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So let's actually have a look at the

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code, to see what's gone wrong here. So

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the actual problem is caused by the test

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in the FAB's onClick method - and

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this is the code here, basically line

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46. So we've used readGranted here, to

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store whether we have access or not,

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but we haven't updated it after going

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into the settings. So consequently, it

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actually failed there and returned false,

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and we weren't able to get access to our

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contacts, until we closed down the app and

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started it again. Now I'm not going to

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say never store state in a variable, like

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we've done here, but what I will say is

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think long and hard before doing so.

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Sometimes it can be necessary, but

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generally, it's much tidier to check the

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state when you need it, rather than

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storing it in a field, as we've done here.

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And the problem we've got here, is that

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we check to see if we had access in the

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onCreate method, and set readGranted to

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true or false, to reflect the state of

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our access. But down in the onRequest

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PermissionResult callback method, we

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also set it to true. Scroll down and

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have a look at that - this one here, code

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standing on line 91. So we also set that

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to true if access is granted, after

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calling requestPermissions. So that

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means that the app would work, after

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tapping Allow in the dialogue. But our

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code that launches the app's Settings, has

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no way of knowing whether the user

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granted access or not. Now of course, we

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know that they went into the settings

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because we sent them there, but we've got

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no control over what they did, when they

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got into the settings. So it's very

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tempting to store things like, whether

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you have a particular permission, and

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it's also very common. But once you start

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doing that, you'll find yourself adding

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more code to keep the variable

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up-to-date as state changes. We saw

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earlier that the Snackbar's onClick

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method ends while the user is still in

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the Settings, so we don't really have a

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convenient way to check the permissions

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again. So a good rule is, if you want to

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know the state of your environment, then

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check it each time you need to know,

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rather than storing that state in a

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field. So don't store the state, because

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you'll end up struggling to keep your

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stored value up-to-date. Alright, so how

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do we go about fixing that? Well let's

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work on that, in the next video.