how can I show alert message after upload file

[luoganghua]

I want to show a message to tell user that uploading file is finished.
But it did not show.
The source is following.
net.POST(url, params: params, successHandler: {responseData in
let localNotification = UILocalNotification()
localNotification.alertBody = "finished!"
UIApplication.sharedApplication().presentLocalNotificationNow(localNotification)
}, failureHandler: { error in
// 失敗
let localNotification = UILocalNotification()
localNotification.alertBody = "error!"
UIApplication.sharedApplication().presentLocalNotificationNow(localNotification)

})