在Kotlin中使用这种结构是个好主意

companion object Run {
   fun after(delay: Long, process: () -> Unit) {
      Handler(Looper.getMainLooper()).postDelayed({
          process()
      }, delay)
   }
}

稍后称为

Run.after(SPLASH_TIME_OUT) {
   val action = SplashFragmentDirections.actionSplashFragmentToLogin()
   v.findNavController().navigate(action)
}

在Handler构造函数中提供一个循环器

Handler(Looper.getMainLooper())

使用Executor而不是handler获取更多信息。 使用ScheduledExecutorService实现post delay:

ScheduledExecutorService worker = Executors.newSingleThreadScheduledExecutor();
Runnable runnable = () -> {
    public void run() {
        // Do something
    }
};
worker.schedule(runnable, 2000, TimeUnit.MILLISECONDS);

使用这个

Looper.myLooper()?.let {
    Handler(it).postDelayed({
        //Your Code
    },2500)
}

根据文档(https://developer.android.com/reference/android/os/Handler#Handler()):

Implicitly choosing a Looper during Handler construction can lead to bugs where operations are silently lost (if the Handler is not expecting new tasks and quits), crashes (if a handler is sometimes created on a thread without a Looper active), or race conditions, where the thread a handler is associated with is not what the author anticipated. Instead, use an Executor or specify the Looper explicitly, using Looper#getMainLooper, {link android.view.View#getHandler}, or similar. If the implicit thread local behavior is required for compatibility, use new Handler(Looper.myLooper()) to make it clear to readers.

我们应该停止使用没有Looper的构造函数，而是指定一个Looper。

handler()等代码是由Android Studio 4.0.1生成的，例如，当一个全屏活动从头创建时。我知道有人鼓励我们使用Kotlin，我也是这样做的，但是我不时地使用示例项目来实现一个想法。 奇怪的是，当AS实际生成代码时，我们却被AS责骂。这可能是一个有用的学术活动来检查错误并修复它们，但也许AS可以为我们爱好者生成新的干净的代码……