Swift 2.0 NSData（contentsOfURL）总是在应用程序中没有，但相同的代码在游乐场中运行良好

Question

我使用以下代码从在线API中获取数据，我在游乐场和我的应用中使用相同的代码。但不知何故，完全相同的代码在游乐场中工作，但在iOS模拟器和iOS 9b1 iPhone上都不起作用（行let dataSource = NSData(contentsOfURL: NSURL(string: "http://api.openweathermap.org/data/2.5/weather?id=5375480")!)在iOS上运行时总是为零。）

class WeatherParser: AnyObject {
    let temp: NSNumber!
    let temp_max: NSNumber!
    let temp_min: NSNumber!
    let humidity: NSNumber!
    var weather_description: String!

    init() {

        var temp: NSNumber! = nil
        var temp_max: NSNumber! = nil
        var temp_min: NSNumber! = nil
        var humidity: NSNumber! = nil
        var weather_description: String!

        let dataSource = NSData(contentsOfURL: NSURL(string: "http://api.openweathermap.org/data/2.5/weather?id=5375480")!)

        if dataSource == nil {
            print("nil")
        }
        if dataSource != nil {
            do {
                let parsedObject: AnyObject? = try! NSJSONSerialization.JSONObjectWithData(dataSource!, options: NSJSONReadingOptions.AllowFragments) as? NSDictionary
                if parsedObject != nil {
                    let dataFromKey_main = parsedObject!["main"] as! NSDictionary
                    temp = dataFromKey_main["temp"] as! NSNumber
                    temp_max = dataFromKey_main["temp_max"] as! NSNumber
                    temp_min = dataFromKey_main["temp_min"] as! NSNumber
                    humidity = dataFromKey_main["humidity"] as! NSNumber

                    let weatherArrayFromSource = parsedObject!["weather"] as? NSArray
                    for dataInArray in weatherArrayFromSource! {
                        if let objs = dataInArray as? NSDictionary {
                            weather_description = objs["description"] as! String
                        }
                    }

                }
            }
        }

        self.temp = temp
        self.temp_max = temp_max
        self.temp_min = temp_min
        self.humidity = humidity
        self.weather_description = weather_description
    }
}

由于我使用与Xcode 6.3.2相同的api url for iOS 8项目，我知道网址正常工作，并且与API密钥无关，因此我不知道＆＃39继续