Objective c 带有tvOS构建目标的目标C中的AVPlayerItem.externalMetaData
我正在为一个tvOS应用程序实现一个功能,但它一直在使用无法识别的选择器崩溃 该应用程序在objc中有一个Objective c 带有tvOS构建目标的目标C中的AVPlayerItem.externalMetaData,objective-c,avfoundation,tvos,avkit,Objective C,Avfoundation,Tvos,Avkit,我正在为一个tvOS应用程序实现一个功能,但它一直在使用无法识别的选择器崩溃 该应用程序在objc中有一个VideoPlayerBase类,iOS的VideoPlayerController.swift和tvOS的VideoPlayerController.swift都继承自基类。加载视频后,我需要设置AVPlayerItem.externalMetaData。但是,当我尝试调用AVPlayerItem.externalMetaData时,它崩溃了 如果我在BasePlayerControlle
VideoPlayerBase
类,iOS的VideoPlayerController.swift
和tvOS的VideoPlayerController.swift
都继承自基类。加载视频后,我需要设置AVPlayerItem.externalMetaData。但是,当我尝试调用AVPlayerItem.externalMetaData时,它崩溃了
如果我在BasePlayerController.m
中设置断点,并在控制台中执行po player.currecitem.externalMetaData
,我将得到此错误
错误:在类型为的对象上找不到属性“externalMetadata”
“AVPlayerItem*”
错误:1解析表达式时出错
然后它将与这条线相撞
self.playerController.player.currentItem?.externalMetadata = episode.metadataItems
调用堆栈:
2016-10-28 09:51:33.808 App[14081:103783] -[AVPlayerItem setExternalMetadata:]: unrecognized selector sent to instance 0x608000214e10
2016-10-28 09:51:33.827 App[14081:103783] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[AVPlayerItem setExternalMetadata:]: unrecognized selector sent to instance 0x608000214e10'
*** First throw call stack:
(
0 CoreFoundation 0x0000000109b00b1b __exceptionPreprocess + 171
1 libobjc.A.dylib 0x000000010920421e objc_exception_throw + 48
2 CoreFoundation 0x0000000109b702d4 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132
3 CoreFoundation 0x0000000109a863e5 forwarding + 1013
4 CoreFoundation 0x0000000109a85f68 _CF_forwarding_prep_0 + 120
5 ***App 0x0000000105baebd0 TFC6AMCApp21VideoPlayerController21playerDidStartPlayingfT_T + 848
6 ***App 0x0000000105baec72 TToFC6AMCApp21VideoPlayerController21playerDidStartPlayingfT_T + 34
7 ***App 0x0000000105b33e38 -[PlayerController play] + 216
8 ***App 0x0000000105b364e8 __42-[PlayerController playerReadyForPlayback]_block_invoke + 952
9 libdispatch.dylib 0x000000010a5c1980 _dispatch_call_block_and_release + 12
10 libdispatch.dylib 0x000000010a5eb0cd _dispatch_client_callout + 8
11 libdispatch.dylib 0x000000010a5cb8d6 _dispatch_main_queue_callback_4CF + 406
12 CoreFoundation 0x0000000109ac4cc9 CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE + 9
13 CoreFoundation 0x0000000109a8a75d __CFRunLoopRun + 2205
14 CoreFoundation 0x0000000109a89c64 CFRunLoopRunSpecific + 420
15 GraphicsServices 0x000000010d12da6f GSEventRunModal + 161
16 UIKit 0x00000001067eb612 UIApplicationMain + 159
17 ***App 0x0000000105b91562 main + 114
18 libdyld.dylib 0x000000010a637749 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
但是,如果我在self.playerController.player.currentItem?行之前或线上设置断点,并在控制台po self.playerController.player.currentItem?中执行po
。我去拿这个
(lldb) po self.playerController.player.currentItem?.externalMetadata
▿ Optional<Array<AVMetadataItem>>
- Some : 0 elements
(lldb)po self.playerController.player.currentItem?.externalMetadata
▿ 可选的
-部分:0个元素
从这条线路继续下去不会使任何事情崩溃强>
我知道externalMetadata
属性是一个仅用于tvOS的属性,我在objc文件和swift文件中都有AVFoundation
,AVKit
导入
我昨天花了一整天的时间没有解决这个问题:(您需要包装行,其中包含AVPlayerItem的属性externalMetadata
,如下所示:
#if TARGET_OS_TV
self.playerController.player.currentItem?.externalMetadata = episode.metadataItems
#endif
或者在相应类的目标成员资格部分中仅选择tvOStarget您需要换行,其中包含AVPlayerItem
的属性externalMetadata
,如下所示:
#if TARGET_OS_TV
self.playerController.player.currentItem?.externalMetadata = episode.metadataItems
#endif
或者在相应类的目标成员资格部分中仅选择tvOStarget