swift 同步加载图片

import UIKit

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

var window: UIWindow?

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
// Override point for customization after application launch.
self.window!.backgroundColor = UIColor.whiteColor()

self.window!.rootViewController = RootViewController();

self.window!.makeKeyAndVisible()
return true
}
}

import UIKit

class RootViewController: UIViewController {

override func viewDidLoad() {
super.viewDidLoad()

let imageView = UIImageView.init(frame: UIScreen.mainScreen().bounds);
imageView.backgroundColor = UIColor.greenColor()
self.view.addSubview(imageView)

let url:NSURL = NSURL.init(string: "http://pic2.ooopic.com/11/86/60/84bOOOPIC13.jpg")!
let data:NSData = NSData(contentsOfURL: url)!
let image = UIImage(data: data)!
imageView.image = image

}

}