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iOS

Austin Murtha
Austin Murtha
4,843 Points
Posted by Austin Murtha
Austin Murtha
4,843 Points

Getting return from JSON request Swift

I am trying to add a JSON request to my app, and get back one value. The query is working, but I am not sure how to get the value out of the function.

https://gist.github.com/austinmurtha/6d27fa817fc387316116

1 Answer

Unsubscribed User
Unsubscribed User
11,496 Points
Unsubscribed User
Unsubscribed User
11,496 Points

Hi Austin,

If you've defined it as a property in a view, when you run your function it should update the value of exchangeRate and you can access it from the class name:

yourViewController.exchangeRate or self.exchangeRate.

If you're trying to set a label's text equal to your result, you could just replace the end bit of your code where you set exchangeRate = multiplierRate with:

self.exchangeRateLabel.text = multiplierRate

That would update the label every time you ran the function. (Don't forget to create an @IBOutlet for the label)

Austin Murtha
Austin Murtha
4,843 Points
Austin Murtha
Austin Murtha
4,843 Points

Thanks Grant. I am looking to just get the Variable from json and pull it from the function.

The actual calculation was going to be done somewhere else. However, I do the calculation in the function.

Basically I give the user several currency options, and depending on what they choose it sets the json query. Then I get the value based on the options selected and pass that to the calculation sections.

Unsubscribed User
Unsubscribed User
11,496 Points

If you're defining exchangeRate as a class property, once you run your getCurrencyData function, exchangeRate will have its value set to the JSON value. At that point you just need to reference exchangeRate any time you want to get at that value. If you have some calculation function that you want to use it in, you can pass exchangeRate as an argument:

var adjustedPrice = doCalculation(exchangeRate, exchangeAmount)

You'll need to make sure your calculation function accepts a Double as one of its arguments:

func doCalculation (exchangeRate: Double, exchangeAmount: Double) -> Double {
    let calculatedAmount = exchangeRate * exchangeAmount

    return calculatedAmount
}

Also, you might want to look at https://github.com/SwiftyJSON/SwiftyJSON#usage Parsing JSON in Swift is pretty ugly and using SwiftyJSON would clean up your function a bit!

Austin Murtha
Austin Murtha
4,843 Points
Austin Murtha
Austin Murtha
4,843 Points

Great minds link alike. I have been doing the swiftyJson tutorial since I ran into this issue. let me try would you have described below.

thanks

Austin Murtha
Austin Murtha
4,843 Points
Austin Murtha
Austin Murtha
4,843 Points

So when I added return multiplieRate I get an error on line 20 that says double not convertible to void. i believe this is due to the completion handler, but not sure how to resolve.

If I add remote mutiplierRate on line 29 it says unresolved identifier multiplierRate

https://gist.github.com/austinmurtha/09ff3947a3f8417d821d

Thanks

Austin Murtha
Austin Murtha
4,843 Points
Austin Murtha
Austin Murtha
4,843 Points

So when I added return multiplieRate I get an error on line 20 that says double not convertible to void. i believe this is due to the completion handler, but not sure how to resolve.

If I add remote mutiplierRate on line 29 it says unresolved identifier multiplierRate

https://gist.github.com/austinmurtha/09ff3947a3f8417d821d

Thanks