CODEWITHSUNDEEP
iosxcodeswiftcore-motion
Kashif
Kashif

Reputation: 4632

CoreMotion Basic

import UIKit
import CoreMotion

class ViewController: UIViewController {

    @IBOutlet weak var label: UILabel!

    override func viewDidLoad() {
        super.viewDidLoad()
        let manager = CMMotionManager()
        if manager.accelerometerAvailable {
            println("accelerometerAvailable = true")
            manager.accelerometerUpdateInterval = 0.01
            manager.startAccelerometerUpdatesToQueue(NSOperationQueue.mainQueue()) {
                [weak self] (data: CMAccelerometerData!, error: NSError!) in

                println("inside")
                println(data)
                println("x: \(data.acceleration.x)")
                println("y: \(data.acceleration.y)")
                println("z: \(data.acceleration.z)")
                self?.label.text = "Kashif"
                self?.label.text = String(format: "%.2f", data.acceleration.x)
            }
        }
    }
}

I have already linked CoreMotion framework. My console output is only

accelerometerAvailable = true

I am not getting updated label or any of the other console output. What am I missing?

Upvotes: 0

Views: 295

Answers (1)

Nate Cook
Nate Cook

Reputation: 93296

Your CMMotionManager instance is scoped to the viewDidLoad method, so it's being deallocated after the method finishes. Thus there's nothing that can send updates to your queue. You want to create the CMMotionManager as a view controller property, or of your app delegate if you'll need it across multiple VCs (since you should only be creating one app-wide).

class ViewController: UIViewController {

    // move the manager out here
    let manager = CMMotionManager()

    // everything else should work fine
    @IBOutlet weak var label: UILabel!

    override func viewDidLoad() {
        super.viewDidLoad()
        if manager.accelerometerAvailable {
            println("accelerometerAvailable = true")
            manager.accelerometerUpdateInterval = 0.01
            manager.startAccelerometerUpdatesToQueue(NSOperationQueue.mainQueue()) {
                [weak self] (data: CMAccelerometerData!, error: NSError!) in

                println("inside")
                println(data)
                println("x: \(data.acceleration.x)")
                println("y: \(data.acceleration.y)")
                println("z: \(data.acceleration.z)")
                self?.label.text = "Kashif"
                self?.label.text = String(format: "%.2f", data.acceleration.x)
            }
        }
    }
}

Upvotes: 2

Related Questions