CODEWITHSUNDEEP
swift
DavidK
DavidK

Reputation: 319

Cannot convert value of type error Swift

I'm following a tutorial on making a simple pedometer app, and I'm getting the following error

Cannot convert value of type '(CMPedometerData!, _) -> Void' to expected argument type 'CMPedometerHandler' (aka '(Optional, Optional) -> ()')

on these lines of code:

if(CMPedometer.isStepCountingAvailable()){
                   let fromDate = NSDate(timeIntervalSinceNow: -86400 * 7)
                   self.pedoMeter.queryPedometerDataFromDate(fromDate, toDate: NSDate()) { (data : CMPedometerData!, error) -> Void in
                       print(data)
                       dispatch_async(dispatch_get_main_queue(), { () -> Void in
                           if(error == nil){
                               self.steps.text = "\(data.numberOfSteps)"
                           }
                       })
                   }
                   self.pedoMeter.startPedometerUpdatesFromDate(midnightOfToday) { (data: CMPedometerData!, error) -> Void in
                       dispatch_async(dispatch_get_main_queue(), { () -> Void in
                           if(error == nil){
                               self.steps.text = "\(data.numberOfSteps)"
                           }
                       })
                   }
               }

Upvotes: 0

Views: 679

Answers (1)

Noah Witherspoon
Noah Witherspoon

Reputation: 57149

The compiler’s telling you that the handler you’re providing is of the wrong type—you have the first parameter as an implicitly-unwrapped optional rather than an optional (it has a ! rather than a ?), and the second parameter has no type at all. In other words, the bits that look like this:

(data : CMPedometerData!, error) -> Void

…should look like this instead:

(data : CMPedometerData?, error: NSError?) -> Void

Upvotes: 5

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