Change view once contact permission is granted - swift

Question

At the moment, I am able to successfully ask the user for their permission to access their Contact information. I am handling this through a switch statement like so:
func requestContactPermissions() {
let store = CNContactStore()
var authStatus = CNContactStore.authorizationStatus(for: .contacts)
switch authStatus {
case .restricted:
print("User cannot grant permission, e.g. parental controls in force.")
exit(1)
case .denied:
print("User has explicitly denied permission.")
print("They have to grant it via Preferences app if they change their mind.")
exit(1)
case .notDetermined:
print("You need to request authorization via the API now.")
store.requestAccess(for: .contacts) { success, error in
if let error = error {
print("Not authorized to access contacts. Error = \(String(describing: error))")
exit(1)
}
if success {
print("Access granted")
}
}
case .authorized:
print("You are already authorized.")
#unknown default:
print("unknown case")
}
}
In the .notDetermined case, this is opening the dialog where I can either click no or yes, granting or denying the application access. This is fine and expected.
What I am looking to do, is change the view if the user clicks yes. Right now, I have the requestContactPermissions function within a button like so:
Button(action: {
withAnimation {
// TODO: Screen should not change until access is successfully given.
requestContactPermissions()
// This is where the view change is occurring.
self.loginSignupScreen = .findFriendsResults
}
})
How might I add in the logic to have the view change once the user has granted the application access to their contacts?

Answer 1

add a completion to the requestContactPermissions function something like this (I trimmed the irrelevant parts for the answer):
func requestContactPermissions(completion: #escaping (Bool) -> ()) {
let store = CNContactStore()
var authStatus = CNContactStore.authorizationStatus(for: .contacts)
switch authStatus {
case .notDetermined:
print("You need to request authorization via the API now.")
store.requestAccess(for: .contacts) { success, error in
if let error = error {
print("Not authorized to access contacts. Error = \(String(describing: error))")
exit(1)
//call completion for failure
completion(false)
}
if success {
//call completion for success
completion(true)
print("Access granted")
}
}
}
}
and then you can determine inside the closure whether the user granted permission or not:
Button(action: {
withAnimation {
// TODO: Screen should not change until access is successfully given.
requestContactPermissions { didGrantPermission in
if didGrantPermission {
//this is the part where you know if the user granted permission:
// This is where the view change is occurring.
self.loginSignupScreen = .findFriendsResults
}
}
}
})