Question

目前，我正在尝试将后台线程简化为我的应用程序中的主线程执行。

我这样做的方式是：

import Foundation

infix operator ~> {}

private let queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0)

func ~> (backgroundClosure: () -> (), mainClosure: () -> ()) {
    dispatch_async(queue) {
        backgroundClosure()
        dispatch_async(dispatch_get_main_queue(), mainClosure)
    }
}

这会让我做类似的事情：

{ println("executed in background thread") } ~> { println("executed in main thread") }

现在......我想扩展这个功能，以便能够dispatch_after到主线程，所以也许我希望它在0.25秒之后调用或者什么。

有没有办法通过以某种方式传递参数来实现这一目标？

理想情况下，我能够实现类似backgroundClosure ~>(0.25) mainClosure的内容，但我怀疑这是可能的

Answer 1

只是一个建议：

infix operator ~> {}

private let queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0)

func ~> (backgroundClosure: () -> (), secondParam: (delayTime:Double, mainClosure: () -> () )) {
    // you can use the `delayTime` here
    dispatch_async(queue) {
        backgroundClosure()
        dispatch_async(dispatch_get_main_queue(), secondParam.mainClosure)
    }
}

使用方法：

{ print("executed in background thread") } ~> (0.25, { print("executed in main thread") })

Answer 2

试试这个：

private let queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0)

infix operator ~>{ associativity left precedence 140}

func ~> (backgroundClosure: ()->() , mainClosure: ()->()) {
dispatch_async(queue) { () -> Void in
    backgroundClosure()
    dispatch_async(dispatch_get_main_queue(), { () -> Void in
        mainClosure()
    })
}}

使用参数创建中缀运算符

2 个答案: