一、dispatch_async(dispatch_queue_t queue, dispatch_block_t block); async表明异步运行,block代表的是你要做的事情,queue则是你把任务交给谁来处理了 (除了async,还有sync,delay,本文以async为例). di
dispatch_time_t popTime= dispatch_time(DISPATCH_TIME_NOW, delayInSeconds *NSEC_PER_SEC); dispatch_after(popTime, dispatch_get_main_queue(),^(void){//code to be executed on the main queue after delay}); dispatch_queue_t 也可以自己定义,如要要自定义queue,可以用dispatch_queue_create方法,示...
2、async和await的关系? async和await是成对出现的。 async出现在方法的声明里,用于批注一个异步方法。光有async是没有意义的。 await出现在方法内部,Task前面。只能在使用async关键字批注的方法中使用await关键字。 private async Task DoSomething(){ await Task.Delay(TimeSpan.FromSeconds(10)); } 1. 2. 3....
1.1.2 非ui线程更新ui控件的方式 runOnUiThread Handler View.postDelay runOnUiThread从名字上可以看出就是专门供其它线程更改ui使用的。...而handler用于不同线程之间的消息传递,可以让线程T1在希望的时刻去通知T2执行某些特定操作。这当然也完全能满足[非ui线程定时通知ui线程更改ui控件状态] ...
HrdelayAutostatEnable HrdelayAutostatDisable 常量 AR Engine 说明 Android AR Engine服务API Java API Package Summary com.huawei.hiar Overview Interface Summary ARTrackable CloudServiceListener FaceHealthServiceListener ServiceListener Class Summary ARAnchor ARAugmentedImage ARAugmentedIma...
HrdelayAutostatEnable HrdelayAutostatDisable 常量 AR Engine 说明 Android AR Engine服务API Java API Package Summary com.huawei.hiar Overview Interface Summary ARTrackable CloudServiceListener FaceHealthServiceListener ServiceListener Class Summary ARAnchor ARAugmentedImage ARAugmented...
问如何使dispatch_async运行EN在下面的代码中，在运行应用程序时，块变量中的日志最近在开发一个关于校园...
Dispatch block after delay:let seconds = 0.5 Async.main(after: seconds) { println("Is called after 0.5 seconds") }.background(after: 0.4) { println("At least 0.4 seconds after previous block, and 0.9 after Async code is called") }...
Dispatch block after delay:let seconds = 0.5 Async.main(after: seconds) { println("Is called after 0.5 seconds") }.background(after: 0.4) { println("At least 0.4 seconds after previous block, and 0.9 after Async code is called") }...
let delayInSeconds = 2.0 let deadline = DispatchTime.now() + delayInSeconds DispatchQueue.main.asyncAfter(deadline: deadline) { print("This will be executed after a delay of \(delayInSeconds) seconds on the main thread.") } 描述如何在Swift中使用DispatchQueue.main.asyncAfter(deadline:进...