IssueTracker

Project: platform/frameworks/support
Branch: androidx-main

commit e782987543a9f8ccd485e970ddc74564b24378db
Author: Vighnesh Raut <vighnesh.raut13@gmail.com>
Date:   Mon Jan 02 15:27:40 2023

    fix: tab row crashes when only 1 tab is added
   
    Bug: b/264018028
   
    Test: Added unit test
   
    Change-Id: I6381dbac304fc1d69d3708c6655f8b595668e93f

M       tv/tv-material/src/androidTest/java/androidx/tv/material/TabRowTest.kt
M       tv/tv-material/src/main/java/androidx/tv/material/TabRow.kt

https://android-review.googlesource.com/2373449

At current now，there is two ways to do the above。

One：
In the NavHostFragment's Activity, override the onBackPress() method,adn if the current NavDestination is MainFragment then just finish the Activity.

@Override
    public void onBackPressed() {
       NavDestination navDestination = mNavController.getCurrentDestination();
        if (navDestination != null
                && navDestination.getId() == R.id.mainFragment) {
            finish();
            return;
        }
        super.onBackPressed();
    }

Two:
Set the to MainFragment action in Navigation_graph app:popUpTo="@id/nav_graph" and app:popUpToInclusive="true"

<?xml version="1.0" encoding="utf-8"?>
<navigation
    android:id="@+id/nav_graph"
    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"
    app:startDestination="@id/splashFragment">

    <fragment
        android:id="@+id/splashFragment"
        android:name="com.ihuman.storydemo.fragment.splash.SplashFragment"
        android:label="fragment_splash"
        tools:layout="@layout/fragment_splash">
        <action
            android:id="@+id/action_splashFragment_to_mainFragment"
            app:destination="@id/mainFragment"
            app:enterAnim="@anim/anim_right_in"
            app:exitAnim="@anim/anim_left_out"
            app:popEnterAnim="@anim/anim_left_in"
            app:popExitAnim="@anim/anim_right_out"
            app:popUpTo="@id/nav_graph"
            app:popUpToInclusive="true"/>
        <action
            android:id="@+id/action_splashFragment_to_guideFragment"
            app:destination="@id/guideFragment"
            app:enterAnim="@anim/anim_right_in"
            app:exitAnim="@anim/anim_left_out"
            app:popEnterAnim="@anim/anim_left_in"
            app:popExitAnim="@anim/anim_right_out"
            app:popUpTo="@id/nav_graph"
            app:popUpToInclusive="true"/>
    </fragment>
       
        <fragment
        android:id="@+id/guideFragment"
        android:name="com.ihuman.storydemo.fragment.guide.GuideFragment"
        android:label="GuideFragment"
        tools:layout="@layout/fragment_guide">
        <action
            android:id="@+id/action_guideFragment_to_mainFragment"
            app:destination="@id/mainFragment"
            app:enterAnim="@anim/anim_right_in"
            app:exitAnim="@anim/anim_left_out"
            app:popEnterAnim="@anim/anim_left_in"
            app:popExitAnim="@anim/anim_right_out"
            app:popUpTo="@id/nav_graph"
            app:popUpToInclusive="true"/>
    </fragment>

    <fragment
        android:id="@+id/mainFragment"
        android:name="com.ihuman.storydemo.fragment.main.MainFragment"
        android:label="fragment_main"
        tools:layout="@layout/fragment_main">
       
    </fragment>
       
</navigation>

Wish for help!