我正在开发一个使用 https://github.com/piemonte 的“播放器”框架的应用程序自从我更新到 swift 3 后,我收到了关于一个特定功能的错误。我不太确定如何修复它,因为我还不是 swift 3 的专业人士。有什么帮助吗? :D
代码(swift 2.3)(请帮我更新到swift 3)
private var PlayerObserverContext = 0
private var PlayerItemObserverContext = 0
private var PlayerLayerObserverContext = 0
override open func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
switch (keyPath, context) {
case (.some(PlayerRateKey), PlayerObserverContext):
true
case (.some(PlayerStatusKey), PlayerItemObserverContext):
true
case (.some(PlayerKeepUp), PlayerItemObserverContext):
if let item = self.playerItem {
self.bufferingState = .ready
self.delegate?.playerBufferingStateDidChange(self)
if item.isPlaybackLikelyToKeepUp && self.playbackState == .playing {
self.playFromCurrentTime()
}
}
let status = (change?[NSKeyValueChangeKey.newKey] as! NSNumber).intValue as AVPlayerStatus.RawValue
switch (status) {
case AVPlayerStatus.readyToPlay.rawValue:
self.playerView.playerLayer.player = self.player
self.playerView.playerLayer.isHidden = false
case AVPlayerStatus.failed.rawValue:
self.playbackState = PlaybackState.failed
self.delegate?.playerPlaybackStateDidChange(self)
default:
true
}
case (.some(PlayerEmptyBufferKey), PlayerItemObserverContext):
if let item = self.playerItem {
if item.isPlaybackBufferEmpty {
self.bufferingState = .delayed
self.delegate?.playerBufferingStateDidChange(self)
}
}
let status = (change?[NSKeyValueChangeKey.newKey] as! NSNumber).intValue as AVPlayerStatus.RawValue
switch (status) {
case AVPlayerStatus.readyToPlay.rawValue:
self.playerView.playerLayer.player = self.player
self.playerView.playerLayer.isHidden = false
case AVPlayerStatus.failed.rawValue:
self.playbackState = PlaybackState.failed
self.delegate?.playerPlaybackStateDidChange(self)
default:
true
}
case (.some(PlayerReadyForDisplay), PlayerLayerObserverContext):
if self.playerView.playerLayer.isReadyForDisplay {
self.delegate?.playerReady(self)
}
default:
super.observeValue(forKeyPath: keyPath, of: object, change: change, context: context)
}
}
最佳答案
我会用 guard
语句打开 context
并像这样匹配:
override open func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
guard let context = context else {
return
}
switch (keyPath, context) {
case (.some(PlayerRateKey), &PlayerObserverContext):
break
case (.some(PlayerStatusKey), &PlayerItemObserverContext):
break
case (.some(PlayerKeepUpKey), &PlayerItemObserverContext):
break
// etc
}
}
应该编译并运行。
我还会将 true
转换为 break
。我不确定 true
的用途。
关于ios - 将 ios 的 "Player"框架更新为 swift 3,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/39400753/