从coredata填充按钮

Question

I'm spending lots of time trying to figure this out and getting no where.

I have an entity with a NSDate attribute, which successfully saves.

How on Earth do I fetch the NSDate from the store(year only section) and make it populate the text on a button. so the button can be pressed later and taken to another View Controller/Table View Controller.

I have spent hours trying to figure this out, I'm totally stuck can't find any examples.

Does anyone have the time to help with this please. Using Swift (hopefully I have formated this question correctly, bit of a noob here) Thank you for looking

//year button
@IBAction func btnYear(sender: AnyObject) {

  //APP DEL REFERANCE
  var appdel: AppDelegate = (UIApplication.sharedApplication().delegate as AppDelegate)
  var context: NSManagedObjectContext = appdel.managedObjectContext!
  let ent = NSEntityDescription.entityForName("FilmInfo", inManagedObjectContext: context)!

  // fetch request
  var request = NSFetchRequest(entityName: "FilmInfo")
  request.returnsObjectsAsFaults = false

Answer 1

First, get the date from your data.

object.date

Then, format it so you can display it on the button.

var formatter = NSDateFormatter()
formatter.dateStyle= .ShortStyle 
let buttonTitle = formatter.stringFromDate(object.date)

Finally assign the title to the button

button.setTitle(buttonTitle, forState: .Normal)

To get to the object in the first place, fetch it. Don't forget to execute your fetch request.

var request = NSFetchRequest(entityName: "FilmInfo")
request.predicate = NSPredicate(format:"id = %@", aFilmInfoID) // example
request.fetchLimit = 1
let results = context.executeFetchRequest(request, error:nil)! as [FilmInfo]
let object = results.first!

Answer 2

You need to execute your fetch request in your context.

var resultsArray = context.executeFetchRequest(request,nil)
if let arr = resultsArray {
    //we have some results
    var firstObject: FilmInfo = arr[0] as FilmInfo
    var date = firstObject.date
}

If you are interested in only one object you can always set request.fetchLimit = 1

Getting more advanced you can also fetch only the date property:

fetch.propertiesToFetch = ["date"]
fetch.resultType = .DictionaryResultType