@IBAction func addButton(_ sender: UIButton) {


        if let text = self.addWeight.text{
            if let date = self.addDate.text{

                self.saveTaskWithName(name: text, date: date, completionHandler: { (success) in
                    // data save successfully
                    print("**** TASK ADDED *******")
                })

        }
    }
}


func saveTaskWithName(name:String,date:String, completionHandler:@escaping ((_ success:Bool)->Void)){
        let dict = ["weight": name, "date" : date] as [String : Any]
        if let userid = Auth.auth().currentUser?.uid{
            self.ref.child("WeightTracker/(userid)").childByAutoId().setValue(dict) { (error, reference) in

                if let err = error{
                    print(err.localizedDescription)
                }else{
                    // data save successfully
                    completionHandler(true)
                }
            }

        }
    }