如何理解和修复这个错误？

Question

2011-04-20 18:38:41.347 RIE[1683:607] -[UICGColor _shouldContinuePlaybackInBackground]: unrecognized selector sent to instance 0x28db10 
2011-04-20 18:38:41.417 RIE[1683:607] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UICGColor _shouldContinuePlaybackInBackground]: unrecognized selector sent to instance 0x28db10' 
*** Call stack at first throw: 
(
    0 CoreFoundation      0x342ed64f __exceptionPreprocess + 114 
    1 libobjc.A.dylib      0x35570c5d objc_exception_throw + 24 
    2 CoreFoundation      0x342f11bf -[NSObject(NSObject) doesNotRecognizeSelector:] + 102 
    3 CoreFoundation      0x342f0649 ___forwarding___ + 508 
    4 CoreFoundation      0x34267180 _CF_forwarding_prep_0 + 48 
    5 MediaPlayer       0x344628b7 -[MPMoviePlayerViewController _moviePlayerViewController_applicationDidEnterBackgroundNotification:] + 42 
    6 Foundation       0x333b5183 _nsnote_callback + 142 
    7 CoreFoundation      0x342bc20f __CFXNotificationPost_old + 402 
    8 CoreFoundation      0x34256eeb _CFXNotificationPostNotification + 118 
    9 Foundation       0x333b25d3 -[NSNotificationCenter postNotificationName:object:userInfo:] + 70 
    10 UIKit        0x36364d01 -[UIApplication _handleApplicationSuspend:eventInfo:] + 500 
    11 UIKit        0x362feaf9 -[UIApplication handleEvent:withNewEvent:] + 1916 
    12 UIKit        0x362fe215 -[UIApplication sendEvent:] + 44 
    13 UIKit        0x362fdc53 _UIApplicationHandleEvent + 5090 
    14 GraphicsServices     0x33e58e77 PurpleEventCallback + 666 
    15 CoreFoundation      0x342c4a97 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 26 
    16 CoreFoundation      0x342c683f __CFRunLoopDoSource1 + 166 
    17 CoreFoundation      0x342c760d __CFRunLoopRun + 520 
    18 CoreFoundation      0x34257ec3 CFRunLoopRunSpecific + 230 
    19 CoreFoundation      0x34257dcb CFRunLoopRunInMode + 58 
    20 GraphicsServices     0x33e5841f GSEventRunModal + 114 
    21 GraphicsServices     0x33e584cb GSEventRun + 62 
    22 UIKit        0x36328d69 -[UIApplication _run] + 404 
    23 UIKit        0x36326807 UIApplicationMain + 670 
    24 Motor Show       0x0000219b main + 70 
    25 Motor Show       0x00002150 start + 40 
) 
terminate called after throwing an instance of 'NSException' 
Program received signal: “SIGABRT”. 

Answer 1

很难说只给定堆栈跟踪，但我会建议如下：

1. 在UIApplicationDelegate实施applicationWillResignActive:以确保视频播放暂停或应用程序进入后台之前停止。

2. 创建自定义UIApplication子类在您的应用程序使用，并覆盖_handleApplicationSuspend:eventInfo:方法，使其返回而不传播活动的其他类进一步环比下滑。

3. 找出如何从通知中心取消注册您的MPMoviePlayerViewController组件，以便它不会收到'ApplicationDidEnterBackgroundNotification'。