Sinch-callDidEstablish在接听来自CallKit的电话时未在锁定屏幕上被调用。我已经集成了CallKit，但是没有调用来自锁屏sinch调用委托(delegate)方法的调用来建立调用。我还浏览了iOSSinchDocument它说:-Invoking-[SINCallanswer]whilebeinginthebackgroundispossible.Thecallisnotimmediatelyansweredbuttheoperationisconsideredpendingandthecallansweredoncetheappreturnstothefor