我让我的代码在另一个项目中工作,在具有以下签名的类中：
class ViewController: UIViewController,NSStreamDelegate,UITextFieldDelegate {
然后我将连接移动到它自己的类,所以我可以在每个连接中重用它：
class XMPPConnection: NSObject,NSStreamDelegate
当我这样做时,我将所有viewDidLoad()代码移动到init()中.我还尝试将该init代码放在一个单独的函数中,并在实例化该类之后调用该函数.这并没有改变任何事情.
我可以在2个项目之间切换,旧的和新的,只是为了确保它不是服务器问题,这样做确认它不是.
每次运行应用程序后,结果都不同.它要么不调用HasSpaceAvailable并且只是坐在那里,要么在我的类AppDelegate中的线程1上抛出(lldb)错误：UIResponder,UIApplicationDelegate,FBLoginViewDelegate.这个错误可能与Facebook集成有关,但是对于lldb来说,没什么可看的.但是,对于每次运行,与其他项目不同,从不调用HasSpaceAvailable.
这是NSStreamDelegate的完整代码,因此没有混淆.该类是一种使用XMPP协议的相当标准的连接方法.
import UIKit
import Foundation
class XMPPConnection: NSObject,NSStreamDelegate { //NSObject
var input : NSInputStream?
var output: NSOutputStream?
//let XMLStream: String = "<stream:stream xmlns:stream='http://etherx.jabber.org/streams' version='1.0' xmlns='jabber:client' to='mydomain.com' xml:lang='en' xmlns:xml='http://www.w3.org/XML/1998/namespace'>"
let XMLStream: String = "<stream:stream to='mydomain.com' xmlns='jabber:client' xmlns:stream='http://etherx.jabber.org/streams' version='1.0'>"
var XMLAuth: String?
let XMLStreamEnd: String = "</stream:stream>"
let XMLResource: String = "<iq type='set' id='bind_1'><bind xmlns='urn:ietf:params:xml:ns:xmpp-bind'><resource>OneSide</resource></bind></iq>"
let XMLSession: String = "<iq type='set' id='sess_1'><session xmlns='urn:ietf:params:xml:ns:xmpp-session'/></iq>"
let XMLStartTLS: String = "<starttls xmlns='urn:ietf:params:xml:ns:xmpp-tls'/>";
var messagesToBeSent:[String] = []
var lastSentMessageID = 0
var lastReceivedMessageID = 0
init(facebookID: String) {
super.init()
let username = "admin@mydomain.com" //should hash device ID
let password = "123456" //hash it
var UTF8AuthStr = "\0\(username)\0\(password)".dataUsingEncoding(NSUTF8StringEncoding)
let Base64Str = UTF8AuthStr!.base64EncodedStringWithOptions(NSDataBase64EncodingOptions.fromRaw(0)!)
XMLAuth = "<auth xmlns='urn:ietf:params:xml:ns:xmpp-sasl' mechanism='PLAIN'>\(Base64Str)</auth>"
//println(XMLAuth)
self.connectToSocket("mydomain.com",port: 5222)
send(self.XMLStream)
//send(self.XMLStartTLS)
/*send(self.XMLAuth!)
send(self.XMLStream)
send(self.XMLResource)
send(self.XMLSession)*/
//sendMessage("hi")
}
func connectToSocket(host: String,port: Int) {
NSStream.getStreamsToHostWithName(host,port: port,inputStream: &(self.input),outputStream: &(self.output))
self.input!.delegate = self
self.output!.delegate = self
self.input!.scheduleInRunLoop(NSRunLoop.currentRunLoop(),forMode: NSDefaultRunLoopMode)
self.output!.scheduleInRunLoop(NSRunLoop.currentRunLoop(),forMode: NSDefaultRunLoopMode)
self.input!.open()
self.output!.open()
println("Connected")
//let bytesWritten = self.output!.write(UnsafePointer(data.bytes),maxLength: data.length)
//println(bytesWritten)
}
//The delegate receives this message when a given event has occurred on a given stream.
func stream(theStream: NSStream!,handleEvent streamEvent: NSStreamEvent) {
println("Message received")
switch streamEvent {
case NSStreamEvent.None:
println("NSStreamEvent.None")
case NSStreamEvent.OpenCompleted:
println("NSStreamEvent.OpenCompleted")
case NSStreamEvent.HasBytesAvailable:
println("NSStreamEvent.HasBytesAvailable")
if let inputStream = theStream as? NSInputStream {
//println("is NSInputStream")
if inputStream.hasBytesAvailable {
//println("hasBytesAvailable")
let bufferSize = 1024
var buffer = Array<UInt8>(count: bufferSize,repeatedValue: 0)
var bytesRead: Int = inputStream.read(&buffer,maxLength: bufferSize)
//println(bytesRead)
if bytesRead >= 0 {
lastReceivedMessageID++
var output: String = NSString(bytes: &buffer,length: bytesRead,encoding: NSUTF8StringEncoding)
//println("output is")
println(output)
} else {
println("error")
// Handle error
}
}
}
case NSStreamEvent.HasSpaceAvailable:
println("NSStreamEvent.HasSpaceAvailable")
send(nil) //send next item
//send next message or
//what if there is no next message to send,and instead waiting user input?
case NSStreamEvent.ErrorOccurred:
println("NSStreamEvent.ErrorOccurred")
case NSStreamEvent.EndEncountered:
println("NSStreamEvent.EndEncountered")
default:
println("default")
}
}
func send(message:String?){
if (self.output!.hasSpaceAvailable){ //stream ready for input
//println("true hasSpaceAvailable")
var data:NSData
var thisMessage:String
if message == nil{ // no message specified
if messagesToBeSent.count != 0{ //messages waiting to be sent
thisMessage = messagesToBeSent[0]
data = messagesToBeSent[0].dataUsingEncoding(NSUTF8StringEncoding,allowLossyConversion: false)!
messagesToBeSent.removeAtIndex(0)
}
else{ //no data to be sent
//no message specified and nothing to be sent
return
}
}
else{
thisMessage = message!
data = message!.dataUsingEncoding(NSUTF8StringEncoding,allowLossyConversion: false)!
}
//println("Sent the following")
wait()
let bytesWritten = self.output!.write(UnsafePointer(data.bytes),maxLength: data.length)
lastSentMessageID++
//println(thisMessage)
//println("Message sent to server and response is")
//println(bytesWritten) //int count
}
else{ //steam busy
println("no space available in stream")
if message != nil{
messagesToBeSent.append(message!)
}
}
}
func sendMessage(message:String,from:String,to:String){
let xmlMessage = "<message to='\(to)@mydomain.com' from='\(from)@mydomain.com' type='chat' xml:lang='en'> <body>\(message)</body></message>"
send(xmlMessage)
}
func wait() {
while true {
//println("waiting")
if lastSentMessageID == lastReceivedMessageID {
break
}
NSRunLoop.currentRunLoop().runUntilDate(NSDate(timeIntervalSinceNow: 0.1));
NSThread.sleepForTimeInterval(0.1)
}
}
}
所以我可以看到可能导致这种情况的两件事.要么将它移动到它自己的类中,要么创建它的实例,要么改变继承.考虑到第一种可能性,我正在研究代码的线程：self.input！.scheduleInRunLoop(NSRunLoop.currentRunLoop(),forMode：NSDefaultRunLoopMode)
检查streamStatus.toRaw()后,它显示1是NSStreamStatusopening.我不确定这是否会发生变化.
解决方法
如果XMPPConnection存储在局部变量中,我可以重现问题,
例如
例如
func application(application: UIApplication,didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
let conn = XMPPConnection(facebookID: "...")
return true
}
此方法返回时,实例将被释放.另一方面是流
代表仍指向实例,这会导致崩溃.代表
NSStream的属性声明为
unowned(unsafe) var delegate: NSStreamDelegate?
这是Swift相当于“assign”又名“unsafe_unretained”.因此
设置委托不保留对象,并取消分配对象
不将属性设置为nil(对于弱引用).
如果实例存储在属性中,例如
class AppDelegate: UIResponder,UIApplicationDelegate {
var window: UIWindow?
var conn : XMPPConnection!
func application(application: UIApplication,didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
conn = XMPPConnection(facebookID: "...")
return true
}
// ...
}
然后你的代码在我的测试中正常工作.
