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iOS Enhance a Weather App with Table Views Upgrading Stormy Custom Background Views

Caleb Kleveter
MOD
Caleb Kleveter
Treehouse Moderator 37,862 Points
Posted by Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

Use of unresolved identifier 'kCGGradientDrawsBeforeStartLocation'

In the code snippet for this video that you can find in the teachers notes, I have been getting this error

Use of unresolved identifier 'kCGGradientDrawsBeforeStartLocation'

What could be causing this? Here is the code:

    override func drawRect(rect: CGRect) {
        // Drawing code

        // Background View

        //// Color Declarations
        let lightPurple: UIColor = UIColor(red: 0.377, green: 0.075, blue: 0.778, alpha: 1.000)
        let darkPurple: UIColor = UIColor(red: 0.060, green: 0.036, blue: 0.202, alpha: 1.000)

        let context = UIGraphicsGetCurrentContext()

        //// Gradient Declarations
        let purpleGradient = CGGradientCreateWithColors(CGColorSpaceCreateDeviceRGB(), [lightPurple.CGColor, darkPurple.CGColor], [0, 1])

        //// Background Drawing
        let backgroundPath = UIBezierPath(rect: CGRectMake(0, 0, self.frame.width, self.frame.height))
        CGContextSaveGState(context)
        backgroundPath.addClip()
        CGContextDrawLinearGradient(context, purpleGradient,
            CGPointMake(160, 0),
            CGPointMake(160, 568),
            UInt32(kCGGradientDrawsBeforeStartLocation) | UInt32(kCGGradientDrawsAfterEndLocation))
        CGContextRestoreGState(context)
    }

This Stack Overflow post might help, but I couldn't make sense of it.

Update

I am also getting the error for latitude, longitude, and navBarAttributesDictionary:

func configureView() {
        // Set table view's bakground property
        tableView.backgroundView = BackgroundView()

        // Change the size and font of nav bar text
        if let navBarFont = UIFont(name: "HelveticaNeue-Thin", size: 20.0) {
            let navBarAttributesDictionary: [String: AnyObject]? = [NSForegroundColorAttributeName: UIColor.whiteColor(), NSFontAttributeName: navBarFont]
        }

        navigationController?.navigationBar.titleTextAttributes = navBarAttributesDictionary
    }                                                                   ^ ================ Error Here

And:

        let forecastService = ForecastService(APIKey: forecastAPIKey)
        forecastService.getForecast(latitude, long: longitude) {
            (let currently) in        ^ =========== ^ ================ Error Here
            if let currentWeather = currently {
                dispatch_async(dispatch_get_main_queue()) {

                    if let temperature = currentWeather.temperature {
                        self.currentTemperatureLabel?.text = "\(temperature)º"
                    }

                    if let precipitation = currentWeather.predipProbability {
                        self.currentPrecipitationLabel?.text = "Rain: \(precipitation)%"
                    }

                    if let icon = currentWeather.icon {
                        self.currentWeatherIcon?.image = icon
                    }

                    self.locationLabel.text = "\(self.location)"


                }
            }
        }

    }

Pasan Premaratne , Stone Preston

Pasan Premaratne
Pasan Premaratne
Treehouse Teacher
Pasan Premaratne
Pasan Premaratne
Treehouse Teacher

Ok gimme a bit of time to investigate. Currently publishing a course and then I'll get to it!

Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points
Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

Swift 2.0 Functions? Just got the announcement, and am exited to start!

1 Answer

Pasan Premaratne
STAFF
Pasan Premaratne
Treehouse Teacher
Pasan Premaratne
Pasan Premaratne
Treehouse Teacher

Replace this line of code 

UInt32(kCGGradientDrawsBeforeStartLocation) | UInt32(kCGGradientDrawsAfterEndLocation))
        CGContextRestoreGState(context)

with this 

[.DrawsBeforeStartLocation, .DrawsAfterEndLocation])

Swift 2 introduces a new Option Set Type that changes the syntax.

For the second error, change this line of code

let navBarAttributesDictionary: [NSObject: AnyObject]?

to this 

let navBarAttributesDictionary: [String: AnyObject]?

In Swift 1.2 the API required setting the type of the dictionary as [NSObject:AnyObject]. This has been changed to [String: AnyObject].

Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points
Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

Thanks for the help! The first code block got changed successfully. As for the second one I already had the alternate code.

And do you know what to do about this line?

forecastService.getForecast(latitude, long: longitude)

I am getting the 'Use of unresolved identifier' error for latitude and longitude.

Pasan Premaratne
Pasan Premaratne
Treehouse Teacher
Pasan Premaratne
Pasan Premaratne
Treehouse Teacher

I'm not getting that :/ I downloaded the project files attached to this video and ran the automatic Swift converter. Did you perhaps make a change? I think it should be coordinate.lat and coordinate.long at this point in the code

Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points
Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

That did it! And to fix the issue with the navBarAttributesDictionary, I used the '!' instead of the if statement.