相关疑难解决方法(0)

在调用以下代码时,尝试将"self"传递给swift中的C函数:

var callbackStruct : AURenderCallbackStruct = 
    AURenderCallbackStruct.init(
      inputProc: recordingCallback,
      inputProcRefCon: UnsafeMutablePointer<Void>
    )

在这里将"self"转换为UnsafeMutablePointer类型的理想方法是什么？

在"ViewController.swift"中我创建了这个回调:

func callback(cf:CFNotificationCenter!, 
    ump:UnsafeMutablePointer<Void>, 
    cfs:CFString!, 
    up:UnsafePointer<Void>, 
    cfd:CFDictionary!) -> Void {

}

使用此观察者:

CFNotificationCenterAddObserver(CFNotificationCenterGetDarwinNotifyCenter(), 
    nil, 
    self.callback, 
    "myMESSage", 
    nil, 
    CFNotificationSuspensionBehavior.DeliverImmediately)

导致此编译器错误:

"AC函数指针只能通过对'func'或文字闭包的引用形成"

当我尝试更改闭包中的变量时,我收到此错误:

A C function pointer cannot be formed from a closure that captures context

是否有解决方法或是否仍然可以更改闭包内的变量？

我的代码:

let callback: @convention(c) (readStream: CFWriteStream!, event: CFStreamEventType, data: UnsafeMutablePointer<Void>) -> Void = {
    (readStream, event, data) -> Void in
    switch event {
    case CFStreamEventType.ErrorOccurred:
        self.isError = true
        break
    case CFStreamEventType.EndEncountered:
        self.isRunLoop = false
        break
    case CFStreamEventType.HasBytesAvailable:
        break
    case CFStreamEventType.OpenCompleted:
        break
    case CFStreamEventType.CanAcceptBytes:
        self.bytesWritten = CFWriteStreamWrite(readStream, self.buffer, self.leftOverSize)
        break
    default:
        break
    }
}

let registeredEvents: CFOptionFlags =
    CFStreamEventType.CanAcceptBytes.rawValue |
    CFStreamEventType.HasBytesAvailable.rawValue |
    CFStreamEventType.ErrorOccurred.rawValue |
    CFStreamEventType.EndEncountered.rawValue | …