Vfrdtyky

I couldn't find any information about what happens when the user disables an app's permission while the app is running.

Is the application re-initilized?

I saw that in some apps if a Dialog or BottomSheet is open while I disable the permission, the dialog is no longer displayed when I return to the app.

Can anyone explain what happens in-detail when a permission is denied at runtime? Or does anyone have some useful links for me?

I would be especially interested in which lifecycle events are called when returning to the app.

When a previously granted permission is revoked through settings, the app is force stopped. You can see this by watching your app in the debugger. The app process is marked DEAD as soon as the permission is revoked.

Returning to the app will launch it from the main activity. I've never really looked into why this happens, but I assume it's because when a granted permission is revoked, the user could be deep into the app at a place where it is assumed the permission is granted. When the permission is revoked, there's no way to know if the screen they are currently in is even valid anymore.

Upon returning to the app, the app's state is restored and your current activity will be restarted, similar to a configuration change. If the activity you are in assumes a certain permission is granted, you should probably check that permission again in onCreate() to make sure you have it.

Simply put, That depends on what the app is trying to do when it needs permission.

For example: If we live in a country that requires you to be an adult to watch any video on YouTube, nothing will work with Location permissions denied

Another example: If you want to take photos using your phone via an app, the Camera permission should be permitted.

Under some circumstances, just part functions of app can not be used, but at an Extreme case, app would throw Security Exception and crash.

According to your point :

I saw that in some apps if a Dialog or BottomSheet is open while I
disable the permission, the dialog is no longer displayed when I
return to the app.

There is no lifecycle callback about what you do once permission is denied, but there's method on ActivityCompat which gives you flag if you want to show your own Dialog/BottomSheet

So, you can call shouldShowRequestPermissionRationale() method from ActivityCompat & make your own logic work when it's true.

shouldShowRequestPermissionRationale :

Gets whether you should show UI with rationale for requesting a permission. You should do this only if you do not have the permission and the context in which the permission is requested does not clearly communicate to the user what would be the benefit from granting this permission.

For example,

if you write a camera app, requesting the camera permission would be expected by the user and no rationale for why it is requested is needed.

If however, the app needs location for tagging photos then a non-tech savvy user may wonder how location is related to taking photos. In this case you may choose to show UI with rationale of requesting this permission.

While disabling permission for first time will give you callback in onRequestPermissionResult() method.