Question

我正在尝试将我的项目转换为swift 3并且还有以下错误。我试过做了几件事，但我做不到。

错误

＆＃34;无法转换类型＆＃39;（OpaquePointer，OpaquePointer，LinphoneRegistrationState，UnsafePointer）的值 - ＆gt; （）＆＃39;指定类型＆＃39; LinphoneCoreRegistrationStateChangedCb＆＃39; （又名＆＃39; @convention（c）（可选，可选，_LinphoneRegistrationState，可选＆gt;） - ＆gt;（）＆＃39;）

对于此代码

var registrationStateChanged: LinphoneCoreRegistrationStateChangedCb = {
    (lc: OpaquePointer, proxyConfig: OpaquePointer, state: LinphoneRegistrationState, message: UnsafePointer<Int8>) in

    switch state{
    case LinphoneRegistrationNone: /**<Initial state for registrations */
        NSLog("LinphoneRegistrationNone")

    case LinphoneRegistrationProgress:
        NSLog("LinphoneRegistrationProgress")

    case LinphoneRegistrationOk:
        NSLog("LinphoneRegistrationOk")

    case LinphoneRegistrationCleared:
        NSLog("LinphoneRegistrationCleared")

    case LinphoneRegistrationFailed:
        NSLog("LinphoneRegistrationFailed")

    default:
        NSLog("Unkown registration state")
    }
}

错误

＆＃34;无法转换类型＆＃39;（OpaquePointer，OpaquePointer，LinphoneCallState，_）的值 - ＆gt; （）＆＃39;指定类型＆＃39; LinphoneCoreCallStateChangedCb＆＃39; （又名＆＃39; @convention（c）（可选，可选，_LinphoneCallState，可选＆gt;） - ＆gt;（）＆＃39;）＆＃34;

以下代码

for var callStateChanged: LinphoneCoreCallStateChangedCb = {
    (lc: OpaquePointer, call: OpaquePointer, callSate: LinphoneCallState,  message) in

    switch callSate{
    case LinphoneCallIncomingReceived: /**<This is a new incoming call */
        NSLog("callStateChanged: LinphoneCallIncomingReceived")

        if answerCall{
            ms_usleep(3 * 1000 * 1000); // Wait 3 seconds to pickup
            linphone_core_accept_call(lc, call)
        }

    case LinphoneCallStreamsRunning: /**<The media streams are established and running*/
        NSLog("callStateChanged: LinphoneCallStreamsRunning")

    case LinphoneCallError: /**<The call encountered an error*/
        NSLog("callStateChanged: LinphoneCallError")

    default:
        NSLog("Default call state")
    }}

Answer 1

Swift 3已经改变了很多东西，对指针的可空性的处理是其中之一。

SE-0055 Make unsafe pointer nullability explicit using Optional

通过此更改，没有可空性注释的C指针将作为Optionals导入。

在您的情况下，OpaquePointer - ＆gt; OpaquePointer?，UnsafePointer<Int8> - ＆gt; UnsafePointer<Int8>?。

（OpaquePointer周围还有其他一些变化，但在您的情况下，它们似乎无关紧要。）

Swift很好地推断出闭包参数的类型（当你的代码写成时）。那么，为什么不首先省略闭包中的所有类型注释呢？

这一行：

(lc: OpaquePointer, proxyConfig: OpaquePointer, state: LinphoneRegistrationState, message: UnsafePointer<Int8>) in

为：

lc, proxyConfig, state, message in

而且：

(lc: OpaquePointer, call: OpaquePointer, callSate: LinphoneCallState,  message) in

为：

lc, call, callSate,  message in

尝试转换为swift 3时出现OpaquePointer错误

1 个答案: