只有无参数的构造函数已弃用，现在最好通过loop . getmainlooper()方法在构造函数中指定循环器。

用于Java

new Handler(Looper.getMainLooper()).postDelayed(new Runnable() {
    @Override
    public void run() {
        // Your Code
    }
}, 3000);

将它用于Kotlin

Handler(Looper.getMainLooper()).postDelayed({
    // Your Code
}, 3000)

来源:developer.android.com

Java的答案

我写了一个容易使用的方法。您可以在项目中直接使用此方法。delayTimeMillis可以是2000，这意味着该代码将在2秒后运行。

private void runJobWithDelay(int delayTimeMillis){
    new Handler(Looper.getMainLooper()).postDelayed(new Runnable() {
        @Override
        public void run() {
            //todo: you can call your method what you want.
        }
    }, delayTimeMillis);
}

只有无参数的构造函数已弃用，现在最好通过loop . getmainlooper()方法在构造函数中指定循环器。

用于Java

new Handler(Looper.getMainLooper()).postDelayed(new Runnable() {
    @Override
    public void run() {
        // Your Code
    }
}, 3000);

将它用于Kotlin

Handler(Looper.getMainLooper()).postDelayed({
    // Your Code
}, 3000)

来源:developer.android.com

协程 Kotlin

private val SPLASH_SCREEN_TIME_OUT_CONST: Long = 3000

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_splash)
    window.setFlags(
        WindowManager.LayoutParams.FLAG_FULLSCREEN,
        WindowManager.LayoutParams.FLAG_FULLSCREEN
    )
    GlobalScope.launch {
        delay(SPLASH_SCREEN_TIME_OUT_CONST)
        goToIntro()
    }

}

private fun goToIntro(){
    startActivity(Intent(this, IntroActivity::class.java))
    finish()
}

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);

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。