- 介绍
1.RunLoop 类提供一些接口管理输入源对象
2.RunLoop 对象处理像键盘,鼠标等事件,以及Port和NSConnection 对象,还处理Timer 事件
*使用须知
1.不能自己创建或者管理RunLoop对象,因为每个线程都会在需要的时候自动创建属于自己的RunLoop 对象,我们可以通过current()方法进入当前线程的run loop
2.RunLoop 没有考虑线程安全,所以前往不要在其他线程调用当前线程的RunLoop,会造成意想不到的错误
方法深入研究
- a.获取当前线程
let runloop = RunLoop.current
print(runloop)
运行结果:
<CFRunLoop 0x608000362ac0 [0x10ed21c70]>{wakeup port = 0x650b, stopped = false, ignoreWakeUps = true,
current mode = (none),
common modes = <CFBasicHash 0x60800004ac20 [0x10ed21c70]>{type = mutable set, count = 1,
entries =>
2 : <CFString 0x10ecf98e0 [0x10ed21c70]>{contents = "kCFRunLoopDefaultMode"}
}
,
common mode items = (null),
modes = <CFBasicHash 0x60800004b8e0 [0x10ed21c70]>{type = mutable set, count = 1,
entries =>
2 : <CFRunLoopMode 0x6080001960a0 [0x10ed21c70]>{name = kCFRunLoopDefaultMode, port set = 0x6603, queue = 0x608000362d00, source = 0x6080001d9140 (not fired), timer port = 0x6803,
sources0 = (null),
sources1 = (null),
observers = (null),
timers = (null),
currently 499832817 (5030729704206) / soft deadline in: 1.8446739e+10 sec (@ -1) / hard deadline in: 1.8446739e+10 sec (@ -1)
},
}
}
- b.RunLoop 转换成 CFRunLoop()
runloop.getCFRunLoop()
- 给RunLoop 中添加一个定时器
DispatchQueue.global().async {
// 给线程起个名字
Thread.current.name = "异步线程"
let runloop = RunLoop.current
let timer = Timer.scheduledTimer(withTimeInterval: 1, repeats: true, block: { (timer) in
print(Thread.current.name)
})
runloop.add(timer, forMode: .commonModes)
/// 必须调用一下run()方法,让其运行
runloop.run()
}
运行:
Optional("异步线程")
Optional("异步线程")
Optional("异步线程")
Optional("异步线程")
Optional("异步线程")
...
- 执行方法或者取消方法
// 向RunLoop 中添加方法 order 代表执行顺序
runloop.perform(#selector(self.input1), target: self, argument:"主线程", order: 2, modes: [RunLoopMode.commonModes])
runloop.perform(#selector(self.input1), target: self, argument:"酷走天涯", order: 2, modes: [RunLoopMode.commonModes])
runloop.perform(#selector(self.input2), target: self, argument:nil, order: 1, modes: [RunLoopMode.defaultRunLoopMode])
/// 移除RunLoop 中 执行对象为Self ,参数为"酷走天涯" 的方法input1()
runloop.cancelPerform(#selector(self.input1), target: self, argument: "酷走天涯")
下面是控制器自定义的几个方法
func input1(_ threadName:String){
print(threadName + "酷走天涯1")
}
func input2(){
print(Thread.current.name! + "酷走天涯2")
}
运行结果:
酷走天涯2
主线程酷走天涯1
提示:
在异步线程没有办法执行方法,具体原因不详
如果我们在异步 将这些方法添加到主线程的RunLoop 去是可以执行的
DispatchQueue.global().async {
Thread.current.name = "异步线程"
let runloop = RunLoop.main
runloop.perform(#selector(self.input1), target: self, argument:"主线程", order: 2, modes: [RunLoopMode.commonModes])
runloop.perform(#selector(self.input1), target: self, argument:"酷走天涯", order: 2, modes: [RunLoopMode.commonModes])
runloop.perform(#selector(self.input2), target: self, argument:nil, order: 1, modes: [RunLoopMode.defaultRunLoopMode])
/// 移除RunLoop 中 执行对象为Self ,参数为"酷走天涯" 的方法input1()
runloop.cancelPerform(#selector(self.input1), target: self, argument: "酷走天涯")
}
还有下面这个方法可以使用
func cancelPerformSelectors(withTarget target: Any)
- 异步RunLoop 执行操作
DispatchQueue.global().async {
Thread.current.name = "异步线程"
let runloop = RunLoop.current
runloop.perform({
print(Thread.current.name! + "执行")
})
runloop.run()
}
运行:
异步线程执行
- 下面这个方法在线程间通讯时会用到
// 1.创建一个NSMachPort 对象 负责接收来自其它线程的消息
let port = NSMachPort()
port.setDelegate(self)
// 2.将port 对象加入到当前线程中去
RunLoop.current.add(port, forMode: .defaultRunLoopMode)
// 其他线程和主线程行进通讯
DispatchQueue.global().async {
// 3.在其它线程创建一个port
let myPort = NSMachPort()
// 4.将port添加到当前线程
RunLoop.current.add(port, forMode: .defaultRunLoopMode)
let array = NSMutableArray(array: [123])
// 5.开始通讯 注意port
port.send(before: Date(), msgid: 1, components: array, from: myPort, reserved: 0)
}
让对象遵守协议NSMachPortDelegate
func handleMachMessage(_ msg: UnsafeMutableRawPointer){
print(msg)
}
运行:
0x00007fff58abe8c0
参考资料