AVAudioPlayer 如何在页面呈现之后按需初始化

在页面中按需初始化 AVAudioPlayer

很多时候我们需要根据页面上内容的情况创建 AVAudioPlayer 对象，已达到降低无谓资源占用等目的。下面我们来看一段代码看起来正确的代码：

override func viewDidAppear(animated: Bool) { super.viewDidAppear(animated) var error: NSError? let player = AVAudioPlayer(data: NSData(contentsOfURL: NSURL(string: "https://dl.django.t.taobao.com/rest/1.0/file?acl=5222dc2f6b41f20dae409a7743dc04fb&cID=40001&fileIds=ytQkYL66QaOs_6tYGSRHQQAAAA8AAQIC&name=13-1.mp3×tamp=1426953600&token=5HwHU8ZKQD-kUh3Yw11nZwAAAAAABSZcAAABw60AAAAPAAEB&uID=")!)!, fileTypeHint: "AVFileTypeMPEGLayer3", error: &error) if let e = error { println(e.debugDescription) } else { player.prepareToPlay() player.play() } }

上面这段代码看起来毫无问题，实际运行以后也是毫无问题，不报错，就是放不出声，非常奇怪。

一步解决奇怪问题

class ViewController: UIViewController { var player: AVAudioPlayer! override func viewDidLoad() { super.viewDidLoad() } override func viewDidAppear(animated: Bool) { super.viewDidAppear(animated) var error: NSError? player = AVAudioPlayer(data: NSData(contentsOfURL: NSURL(string: "https://dl.django.t.taobao.com/rest/1.0/file?acl=5222dc2f6b41f20dae409a7743dc04fb&cID=40001&fileIds=ytQkYL66QaOs_6tYGSRHQQAAAA8AAQIC&name=13-1.mp3×tamp=1426953600&token=5HwHU8ZKQD-kUh3Yw11nZwAAAAAABSZcAAABw60AAAAPAAEB&uID=")!)!, fileTypeHint: "AVFileTypeMPEGLayer3", error: &error) if let e = error { println(e.debugDescription) } else { player.prepareToPlay() player.play() } } }

在此控制器类的顶部事先声明播放器对象，即可成功播放！这个方法对于播放器对象数组、字典依然有效：

var playerArray = Array<AVAudioPlayer>() var playerDictionary = Dictionary<Int, AVAudioPlayer>()

不让对象的内存被自动回收掉即可。

     

转载于:https://www.cnblogs.com/Cheetah-yang/p/4669941.html

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