如果你使用变量作为处理程序和可运行的，然后像这样使用它。

private Handler handler;
private Runnable runnable;

handler = new Handler(Looper.getMainLooper());
    handler.postDelayed(runnable = () -> {
        // Do delayed stuff here
         handler.postDelayed(runnable, 1000);
    }, delay);

你还需要删除onDestroy()中的回调

@Override
public void onDestroy() {
    super.onDestroy();
    if (handler != null) {
        handler.removeCallbacks(runnable);
    }
}

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()和Handler(Handler.)回调回调)构造函数已弃用。因为这可能会导致bug和崩溃。显式使用Executor或Looper。

对于Java

Handler handler = new Handler(Looper.getMainLooper());
handler.postDelayed(new Runnable() {
  @Override
  public void run() {
    //do your work here
   }
}, 1000);

我通常用这个

代码:

Handler(Looper.myLooper() ?: return).postDelayed({
           // Code what do you want
        }, 3000)

截图:

使用这个

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

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……