函数内的访问变量，并将其作为另一个函数的返回swift

Question

import UIKit 

class ViewController: UIViewController, UICollectionViewDelegateFlowLayout, UICollectionViewDataSource { 

    var collectionView: UICollectionView? 

    var instanceOfCustomObject: CustomObject = CustomObject() 
    var accessToken: NSString! 
    var userDefaults: NSUserDefaults! 

    var responseDictionary: NSDictionary! 
// var currentResponse: NSArray! 


    // the range represents integer values 0, 1, and 2 
    // the range now represents integer values 6, 7, and 8 

    let colorWheel = ColorWheel() 
// let parse = Parse() 

// var currentResponse: NSArray? 
// struct photoCount { 
// init(responseDictionary: NSDictionary) { 
// 
//  //  var currentResponse = responseDictionary["data"] as NSDictionary 
// 
//  var currentResponse = responseDictionary.valueForKeyPath("data") as NSArray 
//  var photoCount = currentResponse.count as Int 
//  println(photoCount) 
// } 
// } 
    var photoCount: Int! 

// private let api = "d4984c8cfa78689bd066d82bec820fd5" 



    override func viewDidLoad() { 
     super.viewDidLoad() 

     userDefaults = NSUserDefaults.standardUserDefaults() 
     self.accessToken = userDefaults!.objectForKey("accessToken") as NSString 
     println(self.accessToken) 

     //  instanceOfCustomObject.someProperty = "Hello World" 
//  var accessToken : NSString? = NSString(instanceOfCustomObject.accessToken) 
//  println(accessToken) 
//  instanceOfCustomObject.authorize() 
//  instanceOfCustomObject.simpleAuth() 


     // Do any additional setup after loading the view, typically from a nib. 
     let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout() 
//  layout.sectionInset = UIEdgeInsets(top: 20, left: 0, bottom: 0, right: 0) 
     layout.itemSize = CGSize(width: 124, height: 124) 
     layout.minimumInteritemSpacing = 1.0 
     layout.minimumLineSpacing = 1.0 
     collectionView = UICollectionView(frame: self.view.frame, collectionViewLayout: layout) 
     collectionView!.dataSource = self 
     collectionView!.delegate = self 
     collectionView!.registerClass(Cell.self, forCellWithReuseIdentifier: "Cell") 
     collectionView!.backgroundColor = UIColor.whiteColor() 
     self.view.addSubview(collectionView!) 

     getData() 

    } 

    func getData() -> Void { 
     let baseUrl = NSURL(string:"https://api.instagram.com/v1/users/3/media/recent/?access_token=\(self.accessToken)") 

     let forcastUrl = NSURL(string: "", relativeToURL: baseUrl) 

     //  let data = NSData(contentsOfURL: forcastUrl) 
     //  println(data) 
     let sharedSession = NSURLSession.sharedSession() 
     let downloadTask: NSURLSessionDownloadTask = sharedSession.downloadTaskWithURL(baseUrl, completionHandler: { (location: NSURL!, response: NSURLResponse!, error: NSError!) -> Void in 


      //   var urlContents = NSString.stringWithContentsOfURL(location, encoding: NSUTF8StringEncoding, error: nil) 
      //   println(urlContents) 

      let dataObject = NSData(contentsOfURL: baseUrl) 
      //   println(dataObject) 
      if (error == nil) { 
       let responseDictionary: NSDictionary = NSJSONSerialization.JSONObjectWithData(dataObject, options: nil, error: nil) as NSDictionary 

       var currentResponse = responseDictionary.valueForKeyPath("data") as NSArray 

       //    println(currentResponse) 
       //    self.currentResponse = currentResponse as NSArray 
       self.photoCount = currentResponse.count as Int 
       println(self.photoCount) 

       dispatch_async(dispatch_get_main_queue(), {() -> Void in 

        //     self.temperatureLabel.text = "\(currentWeather.temperature)" 
        //     self.iconView.image = currentWeather.icon! 
        //     self.currentTimeLabel.text = "At \(currentWeather.currentTime!) it is" 
        //     self.humidityLabel.text = "\(currentWeather.humidity)" 
        //     self.percipitationLabel.text = "\(currentWeather.precipProbability)" 
        //     self.summeryLabel.text = "\(currentWeather.summary)" 
        // 
        //     self.refreshActivityIndicator.stopAnimating() 
        //     self.refreshActivityIndicator.hidden = true 
        // 
        //     self.refreshButton.hidden = false 
       }) 

      } else { 

       let networkIssueController = UIAlertController(title: "Error", message: "I got 99 problems but a bitch ain't one", preferredStyle: .ActionSheet) 
       let okButton = UIAlertAction(title: "OK", style: .Default, handler: nil) 
       networkIssueController.addAction(okButton) 
       let cancelButton = UIAlertAction(title: "Cancel", style: .Cancel, handler: nil) 
       networkIssueController.addAction(cancelButton) 

       self.presentViewController(networkIssueController, animated: true, completion: nil) 

       dispatch_async(dispatch_get_main_queue(), {() -> Void in 
        //Stop refresh animation 
        //     self.refreshActivityIndicator.stopAnimating() 
        //     self.refreshActivityIndicator.hidden = true 
        //     self.refreshButton.hidden = false 

       }) 

      } 

     }) 

     downloadTask.resume() 

    } 

在getData（）函数中，名为“currentResponse”的变量检索一个urls数组。那么我算阵列和号码分配给一个名为“光子计数”

func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int { 


//  var photoCount = parse.photoCount(currentResponse) 
     return photoCount 
    } 

我想用“PHOTOCOUNT”变量来告诉我的集合视图功能，它应该有多少段具有可变！有20个网址，所以它应该输出20个方格，但目前的photoCount是零！我是否需要将“photoCount”设置为全局变量？一直困在这个很长时间，请帮助！

Answer 1

您收藏视图的大小分配为无当您的视图控制器加载并且不会随时更新，任何地方。您必须异步重新加载您的集合视图。

在你的getData功能，把这个：

dispatch_async(dispatch_get_main_queue(), { 
    self.photoCount = currentResponse.count as Int 
    self.collectionView.reloadData()   
})