Android导航组件中的处理后退按钮
我想知道如何使用导航控制器正确处理系统后退按钮动作。在我的应用程序中，我有两个片段（例如fragment1和fragment2），并且我在fragment1中有一个动作，目标是fragment2。除一件事情外，其他所有东西都运行良好-当用户在fragment2中按下系统后退按钮时，我想显示一个对话框（例如，使用DialogFragment）以确认退出。实施此行为的最佳方法是什么？如果我在主机片段中使用app:defaultNavHost="true"，则它会自动返回并忽略我的规则。另外，此组件是做什么用的？
我应该使用“流行于”吗？
28 个答案:
答案 0 :(得分：19)
2019年4月25日最新更新
新版本androidx.activity ver. 1.0.0-alpha07带来了一些变化
Android官方指南中的更多说明：Provide custom back navigation
示例：
public class MyFragment extends Fragment {
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// This callback will only be called when MyFragment is at least Started.
OnBackPressedCallback callback = new OnBackPressedCallback(true /* enabled by default */) {
@Override
public boolean handleOnBackPressed() {
// Handle the back button event
}
});
requireActivity().getOnBackPressedDispatcher().addCallback(this, callback);
// The callback can be enabled or disabled here or in handleOnBackPressed()
}
...
}
旧更新
UPD：2019年4月3日
现在将其简化。更多信息here
示例：
requireActivity().getOnBackPressedDispatcher().addCallback(getViewLifecycleOwner(), this);
@Override
public boolean handleOnBackPressed() {
//Do your job here
//use next line if you just need navigate up
//NavHostFragment.findNavController(this).navigateUp();
//Log.e(getClass().getSimpleName(), "handleOnBackPressed");
return true;
}
已弃用（自1.0.0-alpha06版本开始 2019年4月3日）：
自this起，只需在您的片段中使用JetPack实现OnBackPressedCallback即可实现
并将其添加到活动中：
getActivity().addOnBackPressedCallback(getViewLifecycleOwner(),this);
您的片段应如下所示：
public MyFragment extends Fragment implements OnBackPressedCallback {
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
getActivity().addOnBackPressedCallback(getViewLifecycleOwner(),this);
}
@Override
public boolean handleOnBackPressed() {
//Do your job here
//use next line if you just need navigate up
//NavHostFragment.findNavController(this).navigateUp();
//Log.e(getClass().getSimpleName(), "handleOnBackPressed");
return true;
}
@Override
public void onDestroyView() {
super.onDestroyView();
getActivity().removeOnBackPressedCallback(this);
}
}
UPD：
您的活动应扩展AppCompatActivity或FragmentActivity并在Gradle文件中进行：
implementation 'androidx.appcompat:appcompat:{lastVersion}'
答案 1 :(得分：12)
所以，我创建了一个界面
public interface OnBackPressedListener {
void onBackPressed();
}
并由需要处理后退按钮的所有片段实现。在主要活动中，我重写了onBackPressed()方法：
@Override
public void onBackPressed() {
final Fragment currentFragment = mNavHostFragment.getChildFragmentManager().getFragments().get(0);
final NavController controller = Navigation.findNavController(this, R.id.nav_host_fragment);
if (currentFragment instanceof OnBackPressedListener)
((OnBackPressedListener) currentFragment).onBackPressed();
else if (!controller.popBackStack())
finish();
}
因此，如果我的导航主机的顶部片段实现了OnBackPressedListener接口，我将调用其onBackPressed()方法，而在其他地方，我只是弹出堆栈并在返回堆栈为空的情况下关闭应用程序。
答案 2 :(得分：4)
这是应该执行您想要的操作的解决方案，但是我认为这是一个糟糕的解决方案，因为它与Android导航组件的想法（让android处理导航）背道而驰。
覆盖活动中的“ onBackPressed”
override fun onBackPressed() {
when(NavHostFragment.findNavController(nav_host_fragment).currentDestination.id) {
R.id.fragment2-> {
val dialog=AlertDialog.Builder(this).setMessage("Hello").setPositiveButton("Ok", DialogInterface.OnClickListener { dialogInterface, i ->
finish()
}).show()
}
else -> {
super.onBackPressed()
}
}
}
答案 3 :(得分：4)
我在这样的主要活动中写作
override fun onSupportNavigateUp(): Boolean {
return findNavController(R.id.my_nav_host_fragment).navigateUp(appBarConfiguration)
}
答案 4 :(得分：3)
聚会晚了一点，但是在导航组件1.0.0-alpha09的最新版本中，现在有了AppBarConfiguration.OnNavigateUpListener。
有关更多信息，请参阅以下链接： https://developer.android.com/reference/androidx/navigation/ui/AppBarConfiguration.OnNavigateUpListener https://developer.android.com/jetpack/docs/release-notes
答案 5 :(得分：2)
您可以使用OnBackPressedDispatcher提供自定义的后退导航
class MyFragment : Fragment() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
// This callback will only be called when MyFragment is at least Started.
val callback = requireActivity().onBackPressedDispatcher.addCallback(this) {
// Handle the back button event
// and if you want to need navigate up
//NavHostFragment.findNavController(this).navigateUp()
}
// The callback can be enabled or disabled here or in the lambda
}
}
Android官方指南中的更多说明：https://developer.android.com/guide/navigation/navigation-custom-back
答案 6 :(得分：1)
推荐的方法对我有用，但是在更新了库implementation 'androidx.appcompat:appcompat:1.1.0'
实施如下
val onBackPressedCallback = object : OnBackPressedCallback(true) {
override fun handleOnBackPressed() {
// Handle the back button event
}
}
requireActivity().onBackPressedDispatcher.addCallback(this, onBackPressedCallback)
使用Kotlin
答案 7 :(得分：1)
如果您确实想专门处理后退按钮，那么您可以使用@Jurij Pitulja 回答。
但是，如果您想要弹出 SecondFragment（开始片段 FirstFragment）而不返回FirstFragment，那么您可以使用：
Navigation.findNavController(view).popBackStack()
来自SecondFragment。这样，当您从 FirstFragment 按下返回按钮时，您将弹出返回堆栈的 SecondFragmetn，并且不会返回到 SecondFragment。
答案 8 :(得分：1)
只需添加这些行
<iframe width="560" height="315" src="https://www.youtube.com/embed/XQsmrfUbOP8" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen="" class="slick-slide" data-slick-index="1" aria-hidden="true" style="width: 458px;"></iframe>
navController.popBackStack（）只会弹出您的片段，如果这不是您的最后一个片段
答案 9 :(得分：1)
如果您也希望工具栏的“后退”按钮具有相同的行为，只需将其添加到活动中即可：
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == android.R.id.home) {
getOnBackPressedDispatcher().onBackPressed();
return true;
}
return super.onOptionsItemSelected(item);
}
答案 10 :(得分：1)
如果您使用导航组件，请在onCreateView（）方法中遵循以下代码（在此示例中，我只想通过此片段关闭我的应用程序）
OnBackPressedCallback backPressedCallback = new OnBackPressedCallback(true) {
@Override
public void handleOnBackPressed() {
new AlertDialog.Builder(Objects.requireNonNull(getActivity()))
.setIcon(R.drawable.icon_01)
.setTitle(getResources().getString(R.string.close_app_title))
.setMessage(getResources().getString(R.string.close_app_message))
.setPositiveButton(R.string.yes, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
getActivity().finish();
}
})
.setNegativeButton(R.string.no, null)
.show();
}
};
requireActivity().getOnBackPressedDispatcher().addCallback(this, backPressedCallback);
答案 11 :(得分：1)
截至androidx.activity:activity:1.0.0-alpha08（2019年5月7日）
从OnBackPressedDispatcher中检索Activity，并向其中添加一个OnBackPressedCallback。在科特林，您最终会拥有这种美丽：
class MyFragment : Fragment() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
// add callback to dispatcher
requireActivity().onBackPressedDispatcher.addCallback(this) {
// handle back button event
}
}
}
docs提供了更新的解释以及与Java等效的解释。
答案 12 :(得分：0)
这是我的解决方法
对包含androidx.appcompat.app.AppCompatActivity片段的活动使用NavHostFragment。
定义以下接口并将其实现在所有导航目标片段中
interface InterceptionInterface {
fun onNavigationUp(): Boolean
fun onBackPressed(): Boolean
}
在您的活动中覆盖onSupportNavigateUp和onBackPressed：
override fun onSupportNavigateUp(): Boolean {
return getCurrentNavDest().onNavigationUp() || navigation_host_fragment.findNavController().navigateUp()
}
override fun onBackPressed() {
if (!getCurrentNavDest().onBackPressed()){
super.onBackPressed()
}
}
private fun getCurrentNavDest(): InterceptionInterface {
val currentFragment = navigation_host_fragment.childFragmentManager.primaryNavigationFragment as InterceptionInterface
return currentFragment
}
此解决方案的优势在于，导航目标片段无需担心监听器一分离就立即注销。
答案 13 :(得分：0)
ktx 版本：
fun Fragment.handleBackButtonEvent(
onBackPressed: OnBackPressedCallback.() -> Unit
) {
requireActivity().onBackPressedDispatcher.addCallback(viewLifecycleOwner) {
onBackPressed()
}
}
您可以简单地在 Fragmnet 中使用它。
答案 14 :(得分：0)
答案 15 :(得分：0)
尝试一下。我认为这会对您有所帮助。
重写乐趣onBackPressed（）{ 什么时候（mNavController.getCurrentDestination（）!!。getId（））{
R.id.loginFragment -> {
onWarningAlertDialog(this, "Alert", "Do you want to close this application ?")
}
R.id.registerFragment -> {
super.onBackPressed()
}
}
}
onWarningAlertDialog（mainActivity：MainActivity，s： 字符串，s1：字符串）{
val dialogBuilder = AlertDialog.Builder(this) dialogBuilder.setMessage(/*""*/s1) .setCancelable(false) .setPositiveButton("Proceed", DialogInterface.OnClickListener { dialog, id -> finish() }) .setNegativeButton("Cancel", DialogInterface.OnClickListener { dialog, id -> dialog.cancel() }) // create dialog box val alert = dialogBuilder.create() // set title for alert dialog box alert.setTitle("AlertDialogExample") // show alert dialog alert.show() }
答案 16 :(得分：0)
简单地说，在您的 onCreate() 的 Fragment 方法中，在 super.onCreate(savedInstanceState) 之后使用此代码：
// This callback will only be called when MyFragment is at least Started.
val callback = requireActivity().onBackPressedDispatcher.addCallback(viewLifecycleOwner) {
// Handle the back button event
}
答案 17 :(得分：0)
我需要同时支持真正的后退按钮和工具栏后退按钮，并能够在两种情况下覆盖“后退”点击（显示对话框或其他东西）。我在活动和相应的布尔检查（在我的例子中是'onBackPressed'）中做了一个额外的方法：
// Process hardware Back button
override fun onBackPressed() {
if (canCloseActivity()) {
super.onBackPressed()
}
}
// Process toobar Back and Menu button
override fun onSupportNavigateUp(): Boolean {
if (canCloseActivity()) {
return navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
}
return false
}
// Do real check if has unfinished tasks, return false to override activity closing
private fun canCloseActivity(): Boolean {
val currentFragment = navHostFragment.childFragmentManager.primaryNavigationFragment
return when {
currentFragment is MyFragment && currentFragment.onBackPressed() -> false
drawerLayout.isOpen -> {
drawerLayout.close()
false
}
fullScreenPreviewLayout.visibility == View.VISIBLE -> {
closeFullscreenPreview()
false
}
else -> true
}
}
答案 18 :(得分：0)
只需为片段创建扩展功能
fun Fragment.onBackPressedAction(action: () -> Boolean) {
requireActivity().onBackPressedDispatcher.addCallback(viewLifecycleOwner, object :
OnBackPressedCallback(true) {
override fun handleOnBackPressed() {
this.isEnabled = action()
if (!this.isEnabled) {
requireActivity().onBackPressed()
}
}
})
}
然后在片段中将代码放入onCreateView（操作必须返回false才能调用活动onBackPressed）
onBackPressedAction { //do something }
答案 19 :(得分：0)
我搜索了许多线程，但没有一个起作用。终于我找到了一个：
WindowGroup {
ContentView()
.onContinueUserActivity(<your_activity_type_here>) { userActivity in
if let incomingURL = userActivity.webpageURL {
print("Incoming URL is \(incomingURL)")
let linkHandled = DynamicLinks.dynamicLinks().handleUniversalLink(incomingURL) { (dynamicLink, error) in
guard error == nil else{
print("Found an error! \(error!.localizedDescription)")
return
}
if let dynamicLink = dynamicLink {
self.handleIncomingDynamicLink(dynamicLink)
}
}
}
}
}
MainActivity.java @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar mToolbar = findViewById(R.id.topAppBar);
setSupportActionBar(mToolbar);
}
@Override
public boolean onSupportNavigateUp() {
navController.navigateUp();
return super.onSupportNavigateUp();
}
MyFragment.java答案 20 :(得分：0)
如果您正在使用片段或将其添加到按钮单击侦听器中，请使用此选项。这对我有用。
requireActivity().onBackPressed()
在活动检测到用户按下返回键时调用。在调用android.app.Activity＃onBackPressed（）}的默认行为之前，可以让getOnBackPressedDispatcher（）OnBackPressedDispatcher}处理后退按钮。
答案 21 :(得分：0)
如果您的应用程序使用BaseFragment，则可以将onBackPressedDispatcher添加到基本片段中。
//Make a BaseFragment for all your fragments
abstract class BaseFragment : Fragment() {
private lateinit var callback: OnBackPressedCallback
/**
* SetBackButtonDispatcher in OnCreate
*/
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setBackButtonDispatcher()
}
/**
* Adding BackButtonDispatcher callback to activity
*/
private fun setBackButtonDispatcher() {
callback = object : OnBackPressedCallback(true) {
override fun handleOnBackPressed() {
onBackPressed()
}
}
requireActivity().onBackPressedDispatcher.addCallback(this, callback)
}
/**
* Override this method into your fragment to handleBackButton
*/
open fun onBackPressed() {
}
}
通过扩展基本片段覆盖片段中的onBackPressed（）
//How to use this into your fragment
class MyFragment() : BaseFragment(){
private lateinit var mView: View
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
mView = inflater.inflate(R.layout.fragment_my, container, false)
return mView.rootView
}
override fun onBackPressed() {
//Write your code here on back pressed.
}
}
答案 22 :(得分：0)
我尝试了Jurij Pitulja解决方案，但只是找不到getOnBackPressedDispatcher或addOnBackPressedCallback 还使用Kiryl Tkach的解决方案无法找到当前片段，所以这是我的：
interface OnBackPressedListener {
fun onBackPressed(): Boolean
}
override fun onBackPressed() {
val navHostFragment = supportFragmentManager.findFragmentById(R.id.nav_host_fragment)
val currentFragment = navHostFragment?.childFragmentManager!!.fragments[0]
if (currentFragment !is OnBackPressedListener || !(currentFragment as OnBackPressedListener).onBackPressed()) super.onBackPressed()
通过这种方式，您可以分段确定活动是否应控制后按。
或者，您对所有活动都具有BaseActivity，可以像这样实现
override fun onBackPressed() {
val navHostFragment = supportFragmentManager.findFragmentById(R.id.nav_host_fragment)
if (navHostFragment != null){
val currentFragment = navHostFragment.childFragmentManager.fragments[0]
if (currentFragment !is AuthContract.OnBackPressedListener ||
!(currentFragment as AuthContract.OnBackPressedListener).onBackPressed()) super.onBackPressed()
} else {
super.onBackPressed()
}
}
答案 23 :(得分：0)
在2.1.0-alpha06
如果您只想在当前片段中处理backpress
requireActivity().onBackPressedDispatcher.addCallback(this@LoginFragment) {
// handle back event
}
对于整个活动
requireActivity().onBackPressedDispatcher.addCallback() {
// handle back event
}
答案 24 :(得分：0)
对于任何寻求Kotlin实现的人，请参见下文。
请注意，OnBackPressedCallback似乎仅用于为内置软件/硬件后退按钮提供自定义后退行为，而不是为操作栏/工具栏中的向上箭头提供后退箭头按钮/主页。为了也覆盖actionbar / toolbar后退按钮的行为，我提供了适用于我的解决方案。如果这是一个错误，或者您知道针对该情况的更好解决方案，请发表评论。
build.gradle
...
implementation "androidx.appcompat:appcompat:1.1.0-rc01"
implementation "androidx.navigation:navigation-fragment-ktx:2.0.0"
implementation "androidx.navigation:navigation-ui-ktx:2.0.0"
...
MainActivity.kt
...
import androidx.appcompat.app.AppCompatActivity
...
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
setContentView(R.layout.activity_main)
...
val navController = findNavController(R.id.nav_host_fragment)
val appBarConfiguration = AppBarConfiguration(navController.graph)
// This line is only necessary if using the default action bar.
setupActionBarWithNavController(navController, appBarConfiguration)
// This remaining block is only necessary if using a Toolbar from your layout.
val toolbar = findViewById<Toolbar>(R.id.toolbar)
toolbar.setupWithNavController(navController, appBarConfiguration)
// This will handle back actions initiated by the the back arrow
// at the start of the toolbar.
toolbar.setNavigationOnClickListener {
// Handle the back button event and return to override
// the default behavior the same way as the OnBackPressedCallback.
// TODO(reason: handle custom back behavior here if desired.)
// If no custom behavior was handled perform the default action.
navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
}
}
/**
* If using the default action bar this must be overridden.
* This will handle back actions initiated by the the back arrow
* at the start of the action bar.
*/
override fun onSupportNavigateUp(): Boolean {
// Handle the back button event and return true to override
// the default behavior the same way as the OnBackPressedCallback.
// TODO(reason: handle custom back behavior here if desired.)
// If no custom behavior was handled perform the default action.
val navController = findNavController(R.id.nav_host_fragment)
return navController.navigateUp(appBarConfiguration) || super.onSupportNavigateUp()
}
}
MyFragment.kt
...
import androidx.activity.OnBackPressedCallback
import androidx.fragment.app.Fragment
...
class MyFragment : Fragment() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
val onBackPressedCallback = object : OnBackPressedCallback(true) {
override fun handleOnBackPressed() {
// Handle the back button event
}
}
requireActivity().getOnBackPressedDispatcher().addCallback(this, onBackPressedCallback)
}
}
可以在https://developer.android.com/guide/navigation/navigation-custom-back
查看官方文档答案 25 :(得分：0)
这是两行代码，可以监听片段中的回压， [TESTED and WORKING]
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/activemodel-6.0.0/lib/active_model/attribute_methods.rb:431:in `method_missing'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/schema/member/instrumentation.rb:93:in `proxy_to_depth'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/schema/member/instrumentation.rb:85:in `call'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/field.rb:248:in `resolve'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:321:in `call'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/schema/middleware_chain.rb:49:in `invoke_core'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/schema/middleware_chain.rb:38:in `invoke'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:129:in `block in resolve_field'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/tracing.rb:62:in `block in trace'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/tracing.rb:76:in `call_tracers'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/tracing.rb:62:in `trace'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:128:in `resolve_field'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:92:in `block in resolve_selection'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:85:in `each'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:85:in `resolve_selection'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:284:in `resolve_value'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:278:in `resolve_value'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:213:in `continue_resolve_field'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:184:in `continue_or_wait'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:263:in `block in resolve_value'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:256:in `each'",
"/Users/xxxx/.rbenv/versions/2.6.3/lib/ruby/gems/2.6.0/gems/graphql-1.9.12/lib/graphql/execution/execute.rb:256:in `resolve_value'",
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答案 26 :(得分：0)
根据您的逻辑，如果您只想关闭当前片段，则必须传递viewLifecycleOwner，代码如下所示：
requireActivity().onBackPressedDispatcher.addCallback(viewLifecycleOwner, object : OnBackPressedCallback(true) {
override fun handleOnBackPressed() {
requireActivity().finish()
}
})
但是，如果您想关闭backPressed上的应用程序，无论是从哪个片段（可能您都不想要！），都不要传递viewLifecycleOwner。另外，如果要禁用后退按钮，请不要在handleOnBackPressed（）内做任何事情，请参见下文：
requireActivity().onBackPressedDispatcher.addCallback(viewLifecycleOwner, object : OnBackPressedCallback(true) {
override fun handleOnBackPressed() {
// do nothing it will disable the back button
}
})
答案 27 :(得分：-1)
我的意见 requireActivity（）。onBackPressed（）
requireActivity().onBackPressed()
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