因为在应用程序处于活动状态时没有显示UIlocalnotification,所以我正在尝试配置UIAlertController并在它出现时播放一些声音.
我在AppDelegate中没有问题来处理通知/创建警报.我的问题涉及声音.实际上,它无法正常播放.
这是我到目前为止：
//...
class AppDelegate: UIResponder,UIApplicationDelegate {
var window: UIWindow?
func application(application: UIApplication,didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
// Override point for customization after application launch.
// Notifications permissions
let types: UIUserNotificationType = UIUserNotificationType.sound | UIUserNotificationType.Alert
let settings: UIUserNotificationSettings = UIUserNotificationSettings(forTypes: types,categories: nil)
application.registerUserNotificationSettings(settings)
return true
}
func application(application: UIApplication!,didReceivelocalnotification notification: UIlocalnotification!) {
let state : UIApplicationState = application.applicationState
var audioPlayer = AVAudioPlayer()
if (state == UIApplicationState.Active) {
// Create sound
var error:NSError?
var audioPlayer = AVAudioPlayer()
AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryAmbient,error: nil)
AVAudioSession.sharedInstance().setActive(true,error: nil)
let soundURL = NSURL(fileURLWithPath: NSBundle.mainBundle().pathForResource("sound",ofType: "wav")!)
audioPlayer = AVAudioPlayer(contentsOfURL: soundURL,error: &error)
if (error != nil) {
println("There was an error: \(error)")
} else {
audioPlayer.preparetoPlay()
audioPlayer.play()
}
// Create alert
let alertController = UIAlertController(title: "Alert title",message: "Alert message.",preferredStyle: .Alert)
let noAction = UIAlertAction(title: "No",style: .Cancel) { (action) in
// ...
}
let yesAction = UIAlertAction(title: "Yes",style: .Default) { (action) in
// ...
}
alertController.addAction(noAction)
alertController.addAction(yesAction)
self.window?.rootViewController?.presentViewController(alertController,animated: true,completion: nil)
}
}
有了这个,玩家通过这一行：audioPlayer.play()
它的播放时间不到一秒钟.就像它突然被解除分配一样(？).
我试过以下两件事：
>在创建警报之前(或在显示警报之后)将AVAudioPlayer状态切换回非活动状态：AVAudioSession.sharedInstance().setActive(false,error：nil).如果我这样做,声音播放正确.但是,这种方法是一种同步(阻塞)操作,因此它会延迟其他事情(声音在声音后显示).显然不是一个好的解决方案.
>将audioPlayer属性(var audioPlayer = AVAudioPlayer())移动到类级别,就在窗口下(var window：UIWindow？).如果我这样做,声音播放正确,警报也正确显示.
我不明白为什么它会这样.我错过了什么吗？这是解决我问题的正确方法吗？
提前感谢所有能帮助我理解/解决这个问题的人.
