IOKit access to various sensors

Question

I need to access the ambient light sensor and get the carrier strength on iOS 11. I know that IOKit provides this information, but how?

Answer 1

To get the signal strength you could try this function:

func carrierSignalStrength() -> Int? {
    let statusBarView = UIApplication.shared.value(forKey: "statusBar") as! UIView
    let foreground = statusBarView.value(forKey: "foregroundView") as! UIView
    var signalStrengthItem: UIView?

    for view in foreground.subviews {
        if view.isKind(of: NSClassFromString("UIStatusBarSignalStrengthItemView")!) {
            signalStrengthItem = view
            break
        }
    }

    if let strength = signalStrengthItem?.value(forKey: "signalStrengthBars") as? Int {
        return strength
    } else {
        return nil
    }
}

Note that this function reads the signal strength from the status bar, if it´s hidden then it will return nil. If you don´t have a service it will also return nil.

To read the ambient light sensor you can use this library, which works good for this purpose.