关于android：如何制作底部导航的导航图？有没有办法修改回栈行为？

How to make a navigation graph for bottom navigation ? and is there a way to modify the back stack behavior?

我是导航架构组件的新手，正在尝试制作 bottom navigation 视图。我真的很困惑我应该如何以正确的方式实现我的导航图。另外，我想让后台堆栈回到"家"片段然后存在而不是导航所有后台堆栈。

我的应用由三个用于底部导航的片段组成。我试图做的是，我已经将图中每个可能组合中的片段链接起来。
结果不是灾难性的，但我仍然不确定这是否是正确的方法。
此外，当我使用设备的后退按钮时，应用程序会在退出应用程序之前浏览我浏览过的每个片段。

我想进行导航，以便对于第一个后退按钮，它导航回第一个片段 - 起点 - 然后对于第二个片段存在应用程序。

这是导航图的代码

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<?xml version="1.0" encoding="utf-8"?>
<navigation xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/nav_graph"
app:startDestination="@id/bottom_navigation_home">

<fragment
android:id="@+id/bottom_navigation_home"
android:name="com.app.albaladinn.view.ui.HomeFragment"
android:label="fragment_home"
tools:layout="@layout/fragment_home">
<action
android:id="@+id/action_homeFragment_to_couponsFragment"
app:destination="@id/bottom_navigation_coupons" />
<action
android:id="@+id/action_homeFragment_to_settingsFragment"
app:destination="@id/bottom_navigation_settings" />
<action
android:id="@+id/action_homeFragment_to_categoriesFragment"
app:destination="@id/bottom_navigation_categories" />
</fragment>
<fragment
android:id="@+id/bottom_navigation_coupons"
android:name="com.app.albaladinn.view.ui.CouponsFragment"
android:label="fragment_coupons"
tools:layout="@layout/fragment_coupons">
<action
android:id="@+id/action_couponsFragment_to_homeFragment"
app:destination="@id/bottom_navigation_home" />
<action
android:id="@+id/action_couponsFragment_to_settingsFragment"
app:destination="@id/bottom_navigation_settings" />
<action
android:id="@+id/action_couponsFragment_to_categoriesFragment"
app:destination="@id/bottom_navigation_categories" />
</fragment>
<fragment
android:id="@+id/bottom_navigation_settings"
android:name="com.app.albaladinn.view.ui.SettingsFragment"
android:label="fragment_settings"
tools:layout="@layout/fragment_settings">
<action
android:id="@+id/action_settingsFragment_to_couponsFragment"
app:destination="@id/bottom_navigation_coupons" />
<action
android:id="@+id/action_settingsFragment_to_homeFragment"
app:destination="@id/bottom_navigation_home" />
<action
android:id="@+id/action_settingsFragment_to_categoriesFragment"
app:destination="@id/bottom_navigation_categories" />
</fragment>
<fragment
android:id="@+id/bottom_navigation_categories"
android:name="com.app.albaladinn.view.ui.CategoriesFragment"
android:label="fragment_categories"
tools:layout="@layout/fragment_categories">
<action
android:id="@+id/action_categoriesFragment_to_couponsFragment"
app:destination="@id/bottom_navigation_coupons" />
<action
android:id="@+id/action_categoriesFragment_to_homeFragment"
app:destination="@id/bottom_navigation_home"
app:popUpToInclusive="false" />
<action
android:id="@+id/action_categoriesFragment_to_settingsFragment"
app:destination="@id/bottom_navigation_settings" />
</fragment>
</navigation>

这是主要活动

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public class MainNavigationActivity extends AppCompatActivity {

BottomNavigationView mainBottomNavigation;
MainBottomNavigationControl mainBottomNavigationControl;
NavController navController;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_navigation);
navController = Navigation.findNavController(this, R.id.frame_container);
mainBottomNavigation = findViewById(R.id.bottom_navigation);
NavigationUI.setupWithNavController(mainBottomNavigation, navController);
mainBottomNavigationControl = new MainBottomNavigationControl();
mainBottomNavigation.setOnNavigationItemSelectedListener(mainBottomNavigationControl);
}

class MainBottomNavigationControl implements
BottomNavigationView.OnNavigationItemSelectedListener {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
switch (item.getItemId()) {
case R.id.bottom_navigation_home:
navController.navigate(R.id.bottom_navigation_home);
return true;
case R.id.bottom_navigation_categories:
navController.navigate(R.id.bottom_navigation_categories);
return true;
case R.id.bottom_navigation_coupons:
navController.navigate(R.id.bottom_navigation_coupons);
return true;
case R.id.bottom_navigation_settings:
navController.navigate(R.id.bottom_navigation_settings);
return true;
default:
return false;
}
}
}
}