我接通EKAuthorizationStatus但即使requestAuthorisation(to:commit:)被调用，并返回真实，没有错误switch语句中的.notDetermined情况下仍然符合并在它的递归产生无限循环后。它驱使我疯了！
我试图找出requestAuthorisation(to:commit:)如何实际工作，因为我感觉这个问题是所有关于并发或东西，但我无法找到任何东西，所以我无法真正原因有关情况。
而且，由于在我的代码递归绝对是这个无限循环的一部分，我想没有递归的方法。但由于EKAuthorizationStatus可能我的应用程序的调用之间改变的事件商店，我要检查它提前反应到所有它的相应规定。所以我会打电话给我的方法用于切换的授权状态，一个用于请求，并处理所有在我的类，我不想为了可读性，安全而且合理的任何错误。
private func confirmAuthorization(for entityType: EKEntityType) throws {
switch EKEventStore.authorizationStatus(for: entityType) {
case EKAuthorizationStatus.notDetermined:
// Request authorisation for the entity type.
requestAuthorisation(for: entityType)
// Switch again.
try confirmAuthorization(for: entityType)
case EKAuthorizationStatus.denied:
print("Access to the event store was denied.")
throw EventHelperError.authorisationDenied
case EKAuthorizationStatus.restricted:
print("Access to the event store was restricted.")
throw EventHelperError.authorisationRestricted
case EKAuthorizationStatus.authorized:
print("Acces to the event store granted.")
}
}
private func requestAuthorisation(for entityType: EKEntityType) {
store.requestAccess(to: entityType) { (granted, error) in
if (granted) && (error == nil) {
DispatchQueue.main.async {
print("User has granted access to \(String(describing: entityType))") // It's being printed over and over
}
} else {
DispatchQueue.main.async {
print("User has denied access to \(String(describing: entityType))")
}
}
}
}
我期待的开关将匹配在首次推出的.notDetermined情况下，它会要求授权。所以，当我通过开关的状态再次应现配不同的情况下，像.authorized或.denied。但实际上它的.notDetermined情况下再次匹配，并访问被授予了个遍。 \>：[
>2019-01-08 12:50:51.314628+0100 EventManager[4452:190572] libMobileGestalt MobileGestalt.c:890: MGIsDeviceOneOfType is not supported on this platform.
>2019-01-08 12:50:54.608391+0100 EventManager[4452:190572] Adding a new event.
>2019-01-08 12:50:54.784684+0100 EventManager[4452:190572] [MC] System group container for systemgroup.com.apple.configurationprofiles path is /Users/***/Library/Developer/CoreSimulator/Devices/********-****-****-****-************/data/Containers/Shared/SystemGroup/systemgroup.com.apple.configurationprofiles
>2019-01-08 12:50:54.785638+0100 EventManager[4452:190572] [MC] Reading from private effective user settings.
>Acces to the event store granted.
>Saved event with identifier: Optional("F8EAC467-9EC2-476C-BF30-45588240A8D0:903EF489-BB52-4A86-917B-DF72494DEA3D")
>2019-01-08 12:51:03.019751+0100 EventManager[4452:190572] Events succsessfully saved.
>User has granted access to EKEntityType
>User has granted access to EKEntityType
>User has granted access to EKEntityType
>[…]
>User has granted access to EKEntityType
>User has granted access to EKEntityType
>User has granted access to EKEntityType
>2019-01-08 12:51:03.291606+0100 EventManager[4452:190572] [Common] _BSMachError: port 26b03; (os/kern) invalid capability (0x14) "Unable to insert COPY_SEND"
>2019-01-08 12:51:03.317800+0100 EventManager[4452:190572] [Common] _BSMachError: port 26b03; (os/kern) invalid capability (0x14) "Unable to insert COPY_SEND"
>User has granted access to EKEntityType
>User has granted access to EKEntityType
>User has granted access to EKEntityType
>[…]
>User has granted access to EKEntityType
>User has granted access to EKEntityType
>User has granted access to EKEntityType
>Acces to the event store granted.
>Preset <EventManager.EventCreationPreset: 0x6000020ca340> needs update.
>Acces to the event store granted.
>Preset <EventManager.EventCreationPreset: 0x6000020ca340> was updated.
>2019-01-08 12:51:03.567071+0100 EventManager[4452:190572] Events succsessfully saved.
>User has granted access to EKEntityType
>User has granted access to EKEntityType
>User has granted access to EKEntityType
>[…]
该requestAuthorisation异步运行，所以在授权对话框甚至被呈现给用户confirmAuthorization越来越再次调用。
一般来说，在这种模式（在异步模式的递归调用东西的欲望）的，该解决方案将是递归调用移动到异步方法的完成处理。但是，在这种情况下，用户获取授权对话框后，他们会接受或拒绝，而且也没有点担心：“如果它仍然没有确定是什么”的状态。因此，底线，需要或在这种情况下期望没有递归。
话虽如此，很显然你希望得到的状态返回给调用者。但错误引发模式是行不通的，因为你需要处理异步情况（这里没有确定的权限，我们需要提出一个确认对话框）。
所以，我建议，而是你用整个完成处理模式：
private func confirmAuthorization(for entityType: EKEntityType, completion: @escaping (EKAuthorizationStatus) -> Void) {
let status = EKEventStore.authorizationStatus(for: entityType)
switch status {
case .notDetermined:
requestAuthorisation(for: entityType, completion: completion)
default:
completion(status)
}
}
private func requestAuthorisation(for entityType: EKEntityType, completion: @escaping (EKAuthorizationStatus) -> Void) {
store.requestAccess(to: entityType) { _, _ in
DispatchQueue.main.async {
completion(EKEventStore.authorizationStatus(for: entityType))
}
}
}
或者，你可以减少到一个单一的方法：
private func confirmAuthorization(for entityType: EKEntityType, completion: @escaping (EKAuthorizationStatus) -> Void) {
let status = EKEventStore.authorizationStatus(for: entityType)
switch status {
case .notDetermined:
store.requestAccess(to: entityType) { _, _ in
DispatchQueue.main.async {
completion(EKEventStore.authorizationStatus(for: entityType))
}
}
default:
completion(status)
}
}
那么你也能：
confirmAuthorization(for: .event) { status in
switch status {
case .authorized:
// proceed
default:
// handle non-authorized process here
}
}
// But, remember, the above runs asynchronously, so do *not*
// put any code contingent upon the auth status here. You
// must put code contingent upon authorization inside the above
// completion handler closure.
//
// Request authorisation for the entity type.
requestAuthorisation(for: entityType)
被产卵的闭合，这是在后台线程中执行。这意味着该计划的继续，这个方法调用的结果将在未来的某一时刻被传递。问题是：
// Switch again.
try confirmAuthorization(for: entityType)
在随即〜执行主线程〜，并产生另一个后台线程。你不等待这些后台线程来完成，调用另一个后台线程等之前。你需要返工逻辑等待requestAuthorisation再次调用confirmAuthorization之前返回的东西...