Permission handling using new ActivityResultContract API introduced in 1.2.0-alpha02 and Fragment 1.3.0-alpha02

PermissionDemoFragment.kt

class PermissionDemoFragment : BaseFragment<PermissionFragmentBinding>(),PermissionCallback {

    private lateinit var permissionObserver: PermissionObserver

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        permissionObserver =
            PermissionObserver(
                requireActivity(),
                PermissionUtils.phoneStateParmission, this
            )

        // These observers will auto unregistered on activity onDestroy.
        lifecycle.addObserver(permissionObserver)
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        permissionObserver.requestPermission() // Trigger permission request
    }

    override fun getBinding(inflater: LayoutInflater,container: ViewGroup?,bundle: Bundle?)
     = PermissionFragmentBinding.inflate(inflater, container, false)

    override fun onPermissionGranted() {
          // perform action to be taken after permission approval.
    }

    override fun onPermissionDenied() {
         // User denied permission,Display meanigful message with retry button.
    }

    override fun onPermissionPermanentlyDenied() {
        // User permanently denied permission, display more detailed message with settings button.
    }
}

PermissionObserver.kt

/**
 * @{Lifecycle aware PermissionHandler, it will automatically unregister when the Activity is destroyed }
 */
class PermissionObserver(
    private val activity: FragmentActivity,
    private val permission: String,
    private val callback: PermissionCallback
) : DefaultLifecycleObserver {

    private lateinit var requestPermissionLauncher: ActivityResultLauncher<String>

    override fun onCreate(owner: LifecycleOwner) {
        requestPermissionLauncher =
            activity.activityResultRegistry.register(permission,
                owner,
                ActivityResultContracts.RequestPermission(),
                ActivityResultCallback<Boolean> { isGranted: Boolean ->
                    if (isGranted) {
                        callback.onPermissionGranted()
                    } else {
                        if (!shouldShowRequestPermissionRationale(activity, permission)) {
                            callback.onPermissionPermanentlyDenied()
                        } else {
                            callback.onPermissionDenied()
                        }
                    }
                })
    }

    fun requestPermission() {
        requestPermissionLauncher.launch(permission)
    }
}

interface PermissionCallback {
    fun onPermissionGranted()
    fun onPermissionDenied()
    fun onPermissionPermanentlyDenied()
}