背景
我在Swift 1.2上成功使用GCDAsyncSocket
(通过桥接头)。
现在的挑战是它需要某种队列,因为它连接的系统一次只能处理和返回一个命令。
因此,如果它背靠背调用方法,例如:
getSystemInfo()
getSystemStatus()
仅通过委托回调返回getSystemInfo()
,因为系统正在忙于处理它,但getSystemStatus()
已成功发送asynchronously
但未由控制器处理。我希望它能够重新进行调用,并在控制器完成处理并返回之前的响应后让它们排队并处理 - 基本上使进程同步。
问题:
正如您在didConnectToHost
委托回调下的示例代码中所见,当它连接到控制器时,它会调用getSystemInfo()
然后调用getSystemStatus()
,它应该调用{ {1}}从系统信息中获取结果后。
我一直在关注getSystemStatus()
,NSCondition
,甚至是GCD,但我不确定最优雅的方法是什么。我不想在混合中添加另一个队列处理器,因为已经有NSOperation
的队列设置。处理这个问题最好,最优雅的方法是什么?
伪类代码:
GCDAsyncSocket
任何建议都会很棒 - 谢谢!
答案 0 :(得分:3)
所以我决定使用NSOperation。
使用以下代码创建了一个名为SyncRequest.swift的类文件:
import Foundation
class SyncRequest : NSOperation {
var socket:GCDAsyncSocket! = nil
var msgData:NSData! = nil
override var concurrent: Bool {
return false
}
override var asynchronous: Bool {
return false
}
private var _executing: Bool = false
override var executing: Bool {
get {
return _executing
}
set {
if (_executing != newValue) {
self.willChangeValueForKey("isExecuting")
_executing = newValue
self.didChangeValueForKey("isExecuting")
}
}
}
private var _finished: Bool = false;
override var finished: Bool {
get {
return _finished
}
set {
if (_finished != newValue) {
self.willChangeValueForKey("isFinished")
_finished = newValue
self.didChangeValueForKey("isFinished")
}
}
}
/// Complete the operation
func completeOperation() {
executing = false
finished = true
}
override func start() {
if (cancelled) {
finished = true
return
}
executing = true
main()
}
override func main() -> (){
println("starting...")
NSNotificationCenter.defaultCenter().addObserver(self, selector: "didReadData:", name: "DidReadData", object: nil)
sendData()
}
func sendData() {
socket.writeData(msgData, withTimeout: -1.0, tag: 0)
println("Sending: \(msgData)")
socket.readDataWithTimeout(-1.0, tag: 0)
}
func didReadData(notif: NSNotification) {
println("Data Received!")
NSNotificationCenter.defaultCenter().removeObserver(self, name: "DidReadData", object: nil)
completeOperation()
}
}
然后,当我需要向控制器发送内容时,我会执行以下操作:
// sync the request to the controller
let queue = NSOperationQueue() // sync request queue
let requestOperation = SyncRequest()
requestOperation.socket = socket // pass the socket to send through
requestOperation.msgData = msgData // pass the msgData to send
queue.maxConcurrentOperationCount = 1
queue.addOperation(requestOperation)
当数据从你处理GCDAsyncSocket" didReadData"的地方进来时,不要忘记发送NSNotification。委派。
public func socket(socket : GCDAsyncSocket!, didReadData data:NSData!, withTag tag:Int){
...
NSNotificationCenter.defaultCenter().postNotificationName("DidReadData", object: data)
...
}