MPMediaPickerControllerDelegate Permission Check Swift - ios

I have the following code in my project to select audio files through 'MPMediaPickerControllerDelegate'. When run the below code, for the first time the user is prompted to grant permission. If the user declines the loading the picker would silently fail.
Is there a way to prompt user to grant permission if they return after declining at first?
I was wondering if it's a bug. Is there any way we can detect the permission of the MPMediaPickerControllerDelegate so that we can decide to show the audio or not.
Below is my code:
let myMediaPickerVC = MPMediaPickerController(mediaTypes: MPMediaType.anyAudio)
myMediaPickerVC.allowsPickingMultipleItems = false
myMediaPickerVC.delegate = self
present(myMediaPickerVC, animated: true, completion: nil)

You have to first check the authorization permission, then run your code if authorizationStatus permission is authorized. If it is not notDetermined then ask for permission. If it denied then show Alert asking user to go to Settings and enable this permission.
MPMediaLibrary.requestAuthorization({(newPermissionStatus: MPMediaLibraryAuthorizationStatus) in
// This code will be called after the user allows or denies your app permission.
switch (permissionStatus) {
case MPMediaLibraryAuthorizationStatus.authorized:
print("permission status is authorized")
case MPMediaLibraryAuthorizationStatus.notDetermined:
print("permission status is not determined")
MPMediaLibrary.requestAuthorization(MPMediaLibraryAuthorizationStatus -> permissionStatus)
case MPMediaLibraryAuthorizationStatus.denied:
print("permission status is denied")
case MPMediaLibraryAuthorizationStatus.restricted:
print("permission status is restricted")
}
})

Related

How to force 'always' location access in iOS app

The app that I'm building needs always location access to work properly. The app basically tracks location and puts it on a map and stuff (details not important, lol).
My goal is this:
Prompt user to enable "always" location access
If always location access has been requested but the user said no, make the app unusable - basically just show a little button that redirects them to settings where they can change that setting.
My AppDelegate.swift is implementing CLLocationManagerDelegate, and the code is as follows:
alreadyRequestedLocationWhenInUse = UserDefaults.standard.bool(forKey: "alreadyRequestedLocationWhenInUse")
alreadyRequestedLocationAlways = UserDefaults.standard.bool(forKey: "alreadyRequestedLocationAlways")
func locationManagerDidChangeAuthorization(_ manager: CLLocationManager) {
switch CLLocationManager.authorizationStatus() {
case .notDetermined:
if (!alreadyRequestedLocationWhenInUse) {
print("Requesting location access 'while in use'.")
self.locationManager.requestWhenInUseAuthorization();
UserDefaults.standard.set(true, forKey: "alreadyRequestedLocationWhenInUse")
alreadyRequestedLocationWhenInUse = true
} else {
promptToChangeLocationSettings()
}
case .restricted, .denied:
print("No Location access")
promptToChangeLocationSettings()
break;
case .authorizedWhenInUse:
if (!alreadyRequestedLocationAlways) {
print("Requesting location access 'Always'.")
self.locationManager.requestAlwaysAuthorization()
UserDefaults.standard.set(true, forKey: "alreadyRequestedLocationAlways")
alreadyRequestedLocationAlways = true
} else {
promptToChangeLocationSettings()
}
break;
case .authorizedAlways:
self.startLocationMonitoring();
break;
default:
self.locationManager.requestAlwaysAuthorization();
return
}
}
where promptToChangeLocationSettings() is a properly working function that takes the user to the settings page for my app.
The problem is that the user isn't prompted to enable "Always location tracking" until they exit the app and come back. They are asked for 'while in use' permissions (and I know that the way it works is they have to say yes to that first), but I want the always prompt to happen right away! In theory, the locationManagerDidChangeAuthorization function should be called AGAIN after the 'while use' authorization is granted, but this does not happen! Why does this not happen? Instead, promptUserToChangeLocationSettings() runs and makes the app unusable BEFORE the user gets the little poup that asks whether they want to enable 'always' location access.
Can someone help me fix this?
By the way, I am using UserDefaults to keep track of whether we have done a location permission request (as the request can only be done once).
A few observations about this flow where we request “when in use” first, and when that's granted, only then request “always” (as discussed in WWDC 2020 What's New in Location):
Make sure you run this on a device, not the simulator. You may not see the subsequent “upgrade ‘when-in-use’ to ‘always’” permission alert when using a simulator.
This feature was introduced in iOS 13.4. Make sure you are not attempting this on an earlier iOS 13 version. On those earlier versions, you won’t see the second alert to upgrade to “always”.
Make sure you don’t have a lingering requestAlwaysAuthorization elsewhere in your code-base that might have put the app in a “provisional always” state. Once in provisional state, you are locked into the provisional flow of 13.0.
I know it isn’t what you’re looking for, but for the sake of future readers, the alternative to the above is the simpler “provisional always” flow introduced in iOS 13.0 (outlined in WWDC 2019's What's New in Core Location). You just call requestAlwaysAuthorization (never calling requestWhenInUseAuthorization). Apple's intent here was to let the user better reason about what’s going on, showing the “when in use” alert while the app is in use and automatically showing the “always” upgrade alert when location services are used while the app isn't running.
This is a solution that got the result I desired:
Firstly: Make a call to locationManagerDidChangeAuthorization(locationManager) in the AppDelegate.swift didFinishLaunchingWithOptions function. I also called it in applicationWillEnterForeground just so that it rechecks every time the app opens.
Secondly, this is my new locationManagerDidChangeAuthorization function. Just need to remove the return/break statements, but I'm just gonna answer this now before I forget:
func locationManagerDidChangeAuthorization(_ manager: CLLocationManager) {
switch CLLocationManager.authorizationStatus() {
case .notDetermined:
UserDefaults.standard.set(false, forKey: "alreadyRequestedAlwaysLocationAccess")
alreadyRequestedAlwaysLocationAccess = false
DispatchQueue.main.async{
self.coreLocationManager.requestWhenInUseAuthorization()
self.locationManagerDidChangeAuthorization(manager)
}
break;
case .restricted, .denied:
print("No Location access")
promptToChangeLocationSettings()
break;
case .authorizedWhenInUse:
if (!alreadyRequestedAlwaysLocationAccess) {
print("Requesting location access 'Always'.")
UserDefaults.standard.set(true, forKey: "alreadyRequestedAlwaysLocationAccess")
alreadyRequestedAlwaysLocationAccess = true
DispatchQueue.main.async{
self.coreLocationManager.requestAlwaysAuthorization()
self.locationManagerDidChangeAuthorization(manager)
}
} else {
promptToChangeLocationSettings()
}
break;
case .authorizedAlways:
self.startLocationMonitoring();
break;
default:
return
}
}

PhotoLibrary access .notDetermined, when denying then enabling

If I deny at first, then go to settings and allow in settings, in both cases the status is notDetermined, instead of denied then authorized.
Why is that happening?
It doesn't save the image when i click "Don't allow", but status becomes .notDetermined not .denied .
It saves, after i go to settings->Photos, uncheck "Never" and check "Add Photos Only". But the status stays .notDetermined, does not become .authorized
func save(){
guard let image = imageView.image else {return}
UIImageWriteToSavedPhotosAlbum(image, self, nil, nil)
let status = PHPhotoLibrary.authorizationStatus()
switch status {
case .authorized:
print("authorized")
return
case .notDetermined:
print("not determined")
case .denied, .restricted:
print("denied or restricted")
//please go to settings and allow access
promptToSettings()
}
}
I am asking permission to save an image to photo library.
When the first time the user tries to save, he gets asked: "App would like to add to Photos" "Don't Allow" "Ok"
If the user denied then tried to save again,i want to check and if the status is .denied, prompt the user to go to settings and allow.
But the code goes to .notDetermined block when the user does not give access the first time. It stays .notDetermined even after in settings the user allows access.
I downloaded your code and ran it. I was able to experience whatever you said. It always returned Not Determined status.
I did a little bit analysis on your code further. Please find my observation below.
In your current code, "PHPhotoLibrary.requestAuthorization" method is not called before reading the authorization status using "PHPhotoLibrary.authorizationStatus" method.
Though "UIImageWriteToSavedPhotosAlbum" in Save method triggers a Photos app permission pop up, it does not help here completely.
So, I called "askForAccessAgain" method in ViewDidLoad method in order to get the permission using "PHPhotoLibrary.requestAuthorization" method first.
After that, whenever i saved the photos using Save method, it returned the correct status, let it be either "Authorized" or "Denied".
If I choose "Never" and "Allow Photos Only", it returned "Denied or Restricted" status. When "Read and Write" is chosen, "authorized" is returned.
So, it looks like, We need to call "PHPhotoLibrary.requestAuthorization" method to get the permission first instead of relying on other Photo access methods ( like UIImageWriteToSavedPhotosAlbum) for getting the permission. Only then, correct status is returned by "PHPhotoLibrary.authorizationStatus".
One more addition info:
App Permissions are retained even after deleting the app and reinstalling it. Just take a look on this as well. It might help you in troubleshooting similar issues in future.
iPad remembering camera permissions after delete—how to clear?
Please let me know if this has resolved your issues.

Does AVCaptureDevice.requestAccessForMediaType only work for undetermined authorization status?

I am checking if an app has permission to use the camera with:
let authStatus = AVCaptureDevice.authorizationStatusForMediaType(AVMediaTypeVideo)
If the authorization status is denied (perhaps the user accidentally did not allow permission the first time when asked), is it possible to show the permission request again?
If authorization has been denied, I am attempting to request permission with:
AVCaptureDevice.requestAccessForMediaType(AVMediaTypeVideo,
completionHandler: { (granted:Bool) -> Void in
if granted {
dispatch_async(dispatch_get_main_queue()) {
self.shootPhoto(UIButton())
}
}
})
But no request for permission is dialog is presented. Does requestAccessForMediaType only work if the authorization status is undetermined?
No this is not possible. In this situation, you will need to explain to the user how to go into Settings and change the permissions.

How to refresh permission after getting access to it

I need to access users Photos, for this I ask for permission. There are possible outcomes :
Permission granted : In this condition application resumes it normal functioning.
Permission Denied : In this case application shows an alert wherein user has option to goToSettings or to just ignore it. If user selects goToSettings and provides access to photos and comes back to application then it still says that permission is not granted. Permissions are only refreshed when I restart my application.
My Question: How to refresh the application's permission settings without restarting my application. Similar problem to my question is posted here.
Edit:
My application is a navigation controller based application and I check for access in my controller's viewDidLoad. I just tried if request permissions are refreshed if I pop and push the controller again. No luck, the results where same - it still said permission denied.
Edit 2 : Code to check for permissions
func requestAccess() -> Void {
PHPhotoLibrary.requestAuthorization {
status in
switch(status) {
case .notDetermined, .denied :
// perform relavent action
break
case .authorized , .restricted :
// perform relavent action
break
}
}
}
iOS kills your app when you changed privacy settings. And after next tap on app's icon your app is started from scratch. application:didFinishLaunching is called and so on. So you don't need to update permissions.
In your AppDelegate you could have logic in applicationDidBecomeActive to re-query the permission store for your updated permissions.
In your viewDidLoad for the view you check permissions on you could observe the notification like so;
NSNotificationCenter.defaultCenter().addObserver(
self,
selector: #selector(yourClass.applicationDidBecomeActive(_:)),
name: UIApplicationDidBecomeActiveNotification,
object: nil)
The code below is Objective-C.
I think you can do this when user tapping a button or something:
PHAuthorizationStatus status = [PHPhotoLibrary authorizationStatus];
if (status == PHAuthorizationStatusNotDetermined) {
// ask for authorization
[PHPhotoLibrary requestAuthorization...
} else if (status == PHAuthorizationStatusAuthorized) {
// continue accessing photos
} else {
// access denied, go to settings if you want
}

How to request for permission before the actual object is initialized?

How can I request for permissions to location, camera, bluetooth etc. without initializing proper object instances?
I want to ask for permissions/authorizations during app's onboarding, then I'd like to initialize CLLocationManager etc afterwards.
I tried Googling it, but failed to find anything relevant. Is it actually possible?
For permissions like location access ,we need a manager instance to show the location access prompt ( refer :http://nshipster.com/core-location-in-ios-8/). These instances can be used only to request access (if you want them to only request for access) and in the future if you want to access the resource or data we can again use these manager instances.
For Example:
CLLocation manager should be used to access user's location, so in first screen if you just want to ask location permission then can use following code
CLLocationManager().requestAlwaysAuthorization() //Requesting always permission
And if you want to access user's location in some other screen you can access it as:
locationManager.startUpdatingLocation() // use delegate methods to handle the values.
So these kind of managers can be initialised only for requesting permission, then can be reinitialised when required.
Here is an article about best way to ask location permissions (same can be applied for other types of permission requests) https://techcrunch.com/2014/04/04/the-right-way-to-ask-users-for-ios-permissions/
For each action do the similar approach
let status = PHPhotoLibrary.authorizationStatus()
switch status {
case .authorized:
case .denied, .restricted :
//handle denied status
case .notDetermined:
// ask for permissions
PHPhotoLibrary.requestAuthorization() { (status) -> Void in
switch status {
case .authorized:
// as above
case .denied, .restricted:
// as above
case .notDetermined: break
// won't happen but still
}
}
}

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