I'm currently making a dictionary app and I'm re-parsing through the json file that contains all the entries of the dictionaries every time I open the app and saving it to CoreData. I was wondering if there is a function in Swift that just runs once when the app is downloaded and then doesn't run again.
What you can do set a NSUserDefaults to check whether it is a first run or not:
let firstRun = NSUserDefaults.standardUserDefaults().boolForKey("firstRun") as Bool
if !firstRun {
//run your function
NSUserDefaults.standardUserDefaults().setBool(true, forKey: "firstRun")
}
Swift 4 example:
In your ViewController
let firstRun = UserDefaults.standard.bool(forKey: "firstRun") as Bool
Then in your viewDidLoad
if firstRun {
//function you want to run normally
} else {
runFirst() //will only run once
}
Then make this function down below
func runFirst() {
print("FIRST RUN!")
UserDefaults.standard.set(true, forKey: "firstRun")
}
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