现在Handler()被弃用了，我应该用什么？

处理程序()

处理程序(Handler.Callback)

谷歌解释了下面的原因。

在构建处理程序时隐含地选择一个Looper 处理程序构建过程中隐式地选择Looper，可能会导致操作被悄悄丢失的错误 丢失（如果处理程序不期望有新的任务并退出）、崩溃 (崩溃（如果有时在一个没有Looper的线程上创建处理程序 活动的线程上创建处理程序），或者竞赛条件，即处理程序所关联的线程 与之相关的线程不是作者所预期的。相反，使用一个执行器或 明确指定Looper，使用Looper#getMainLooper，{link android.view.View#getHandler}，或类似的方法。如果隐含的线程 本地行为是为了兼容，请使用new Handler(Looper.myLooper(), callback)来让读者明白。

Solution 1: 使用一个 Executor

1. 在主线程中执行代码。

// Create an executor that executes tasks in the main thread. 
Executor mainExecutor = ContextCompat.getMainExecutor(this);
// Execute a task in the main thread
mainExecutor.execute(new Runnable() {
    @Override
    public void run() {
        // You code logic goes here.
Kotlin
// Create an executor that executes tasks in the main thread.
val mainExecutor = ContextCompat.getMainExecutor(this)
// Execute a task in the main thread
mainExecutor.execute {
    // You code logic goes here.
2.在一个后台线程中执行代码
// Create an executor that executes tasks in a background thread.
ScheduledExecutorService backgroundExecutor = Executors.newSingleThreadScheduledExecutor();
// Execute a task in the background thread.
backgroundExecutor.execute(new Runnable() {
    @Override
    public void run() {
        // Your code logic goes here.
// Execute a task in the background thread after 3 seconds.
backgroundExecutor.schedule(new Runnable() {
    @Override
    public void run() {
        // Your code logic goes here
}, 3, TimeUnit.SECONDS);
Kotlin
// Create an executor that executes tasks in a background thread.
val backgroundExecutor: ScheduledExecutorService = Executors.newSingleThreadScheduledExecutor()
// Execute a task in the background thread.
backgroundExecutor.execute {
    // Your code logic goes here.
// Execute a task in the background thread after 3 seconds.
backgroundExecutor.schedule({
    // Your code logic goes here
}, 3, TimeUnit.SECONDS)
Note:记住在使用后要关闭执行器。
backgroundExecutor.shutdown(); // or backgroundExecutor.shutdownNow();
3.在一个后台线程中执行代码 and update UI on the main thread.
// Create an executor that executes tasks in the main thread. 
Executor mainExecutor = ContextCompat.getMainExecutor(this);
// Create an executor that executes tasks in a background thread.
ScheduledExecutorService backgroundExecutor = Executors.newSingleThreadScheduledExecutor();
// Execute a task in the background thread.
backgroundExecutor.execute(new Runnable() {
    @Override
    public void run() {
        // Your code logic goes here.
        // Update UI on the main thread
        mainExecutor.execute(new Runnable() {
            @Override
            public void run() {
                // You code logic goes here.
Kotlin
// Create an executor that executes tasks in the main thread. 
val mainExecutor: Executor = ContextCompat.getMainExecutor(this)
// Create an executor that executes tasks in a background thread.
val backgroundExecutor = Executors.newSingleThreadScheduledExecutor()
// Execute a task in the background thread.
backgroundExecutor.execute {
    // Your code logic goes here.
    // Update UI on the main thread
    mainExecutor.execute {
        // You code logic goes here.
Solution 2:通过使用以下构造函数之一明确指定一个Looper。
处理程序(Looper)
Handler(Looper, Handler.Callback)
1.在主线程中执行代码
1.1.带循环器的处理程序
Handler mainHandler = new Handler(Looper.getMainLooper());
Kotlin
val mainHandler = Handler(Looper.getMainLooper())
1.2带循环器的处理程序 and a Handler.Callback
Handler mainHandler = new Handler(Looper.getMainLooper(), new Handler.Callback() {
    @Override
    public boolean handleMessage(@NonNull Message message) {
        // Your code logic goes here.
        return true;
Kotlin
val mainHandler = Handler(Looper.getMainLooper(), Handler.Callback {
    // Your code logic goes here.
2.在一个后台线程中执行代码
2.1.带循环器的处理程序
// Create a background thread that has a Looper
HandlerThread handlerThread = new HandlerThread("HandlerThread");
handlerThread.start();
// Create a handler to execute tasks in the background thread.
Handler backgroundHandler = new Handler(handlerThread.getLooper()); 
Kotlin
// Create a background thread that has a Looper
val handlerThread = HandlerThread("HandlerThread")
handlerThread.start()
// Create a handler to execute tasks in the background thread.
val backgroundHandler = Handler(handlerThread.looper)
2.2.带循环器的处理程序 and a Handler.Callback
// Create a background thread that has a Looper
HandlerThread handlerThread = new HandlerThread("HandlerThread");
handlerThread.start();
// Create a handler to execute taks in the background thread.
Handler backgroundHandler = new Handler(handlerThread.getLooper(), new Handler.Callback() {
    @Override
    public boolean handleMessage(@NonNull Message message) {
        // Your code logic goes here.
        return true;
Kotlin
// Create a background thread that has a Looper
val handlerThread = HandlerThread("HandlerThread")
handlerThread.start()
// Create a handler to execute taks in the background thread.
val backgroundHandler = Handler(handlerThread.looper, Handler.Callback {
    // Your code logic goes here.
Note:记得使用后要松开线。
handlerThread.quit(); // or handlerThread.quitSafely();
3.在一个后台线程中执行代码 and update UI on the main thread.
// Create a handler to execute code in the main thread
Handler mainHandler = new Handler(Looper.getMainLooper());
// Create a background thread that has a Looper
HandlerThread handlerThread = new HandlerThread("HandlerThread");
handlerThread.start();
// Create a handler to execute in the background thread
Handler backgroundHandler = new Handler(handlerThread.getLooper(), new Handler.Callback() {
    @Override
    public boolean handleMessage(@NonNull Message message) {
        // Your code logic goes here.
        // Update UI on the main thread.
        mainHandler.post(new Runnable() {
            @Override
            public void run() {
        return true;
Kotlin
// Create a handler to execute code in the main thread
val mainHandler = Handler(Looper.getMainLooper())
// Create a background thread that has a Looper
val handlerThread = HandlerThread("HandlerThread")
handlerThread.start()
// Create a handler to execute in the background thread
val backgroundHandler = Handler(handlerThread.looper, Handler.Callback {
    // Your code logic goes here.
    // Update UI on the main thread.
    mainHandler.post {