Android Studio中Navigation底部菜单点击无跳转问题求助

在Android Studio中使用View Binding和Navigation组件开发时，点击底部菜单无法切换到导航图中id为saveFragment的页面。

相关代码 #

项目级build.gradle #

buildscript {
    repositories {
        google()
    }
    dependencies {
        def nav_version = "2.5.3"
        classpath("androidx.navigation:navigation-safe-args-gradle-plugin:$nav_version")
    }
}

plugins {
    id 'com.android.application' version '7.3.1' apply false
    id 'com.android.library' version '7.3.1' apply false
    id 'org.jetbrains.kotlin.android' version '1.7.20' apply false
    id 'com.google.dagger.hilt.android' version "2.44" apply false
}

模块级build.gradle #

plugins {
    id 'com.android.application'
    id 'org.jetbrains.kotlin.android'
    id 'kotlin-kapt'
    id "com.google.dagger.hilt.android"
    id "androidx.navigation.safeargs.kotlin"
}

android {
    namespace 'com.example.newsapiclient'
    compileSdk 32

    defaultConfig {
        applicationId "com.example.newsapiclient"
        minSdk 26
        targetSdk 32
        versionCode 1
        versionName "1.0"
        buildConfigField("String","API_KEY", MY_KEY)
        buildConfigField("String","BASE_URL",MY_URL)

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled true
            shrinkResources true
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = '1.8'
    }
    buildFeatures {
        viewBinding =  true
    }
}

dependencies {
    def lifecycle_version = "2.5.1"
    def nav_version = "2.5.3"

    implementation 'androidx.core:core-ktx:1.7.0'
    implementation 'androidx.appcompat:appcompat:1.5.1'
    implementation 'com.google.android.material:material:1.7.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
    implementation 'com.google.code.gson:gson:2.10.1'
    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:1.6.4"
    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-android:1.6.4"

    implementation "com.squareup.retrofit2:retrofit:2.9.0"
    implementation "com.squareup.retrofit2:converter-gson:2.9.0"

    // ViewModel
    implementation("androidx.lifecycle:lifecycle-viewmodel-ktx:$lifecycle_version")
    // ViewModel utilities for Compose
    implementation("androidx.lifecycle:lifecycle-viewmodel-compose:$lifecycle_version")
    // LiveData
    implementation("androidx.lifecycle:lifecycle-livedata-ktx:$lifecycle_version")
    kapt "androidx.lifecycle:lifecycle-compiler:$lifecycle_version"

    implementation("com.google.dagger:hilt-android:2.44")
    kapt("com.google.dagger:hilt-android-compiler:2.44")

    implementation("androidx.navigation:navigation-fragment-ktx:$nav_version")
    implementation("androidx.navigation:navigation-ui-ktx:$nav_version")

    implementation 'com.github.bumptech.glide:glide:4.14.2'
    kapt 'com.github.bumptech.glide:compiler:4.14.2'

    testImplementation 'junit:junit:4.13.2'
    testImplementation "com.squareup.okhttp3:mockwebserver:4.10.0"
    testImplementation "com.google.truth:truth:1.1.3"
    androidTestImplementation 'androidx.test.ext:junit:1.1.5'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
}

导航图nav_graph.xml #

<?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/newsFragment">

    <fragment
        android:id="@+id/newsFragment"
        android:name="com.example.newsapiclient.NewsFragment"
        android:label="fragment_news"
        tools:layout="@layout/fragment_news" >
        <action
            android:id="@+id/action_newsFragment_to_infoFragment"
            app:destination="@id/infoFragment" />
    </fragment>
    <fragment
        android:id="@+id/saveFragment"
        android:name="com.example.newsapiclient.SaveFragment"
        android:label="fragment_save"
        tools:layout="@layout/fragment_save" >
        <action
            android:id="@+id/action_saveFragment_to_infoFragment"
            app:destination="@id/infoFragment" />
    </fragment>
    <fragment
        android:id="@+id/infoFragment"
        android:name="com.example.newsapiclient.InfoFragment"
        android:label="fragment_info"
        tools:layout="@layout/fragment_info" />
</navigation>

MainActivity代码 #

class MainActivity : AppCompatActivity() {

    private lateinit var binding : ActivityMainBinding
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)
        val navHostFragment = supportFragmentManager
            .findFragmentById(R.id.fragmentContainerView)  as NavHostFragment
        val navController = navHostFragment.navController

    }
}

底部菜单bottom_menu.xml #

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">

    <item
        android:id="@+id/newsFragment"
        android:icon="@drawable/ic_baseline_live_tv_24"
        android:title="News Headlines" />
    <item
        android:id="@+id/saveFragment"
        android:icon="@drawable/ic_baseline_save_24"
        android:title="Save News" />
</menu>

解决方案 #

问题核心是未将底部导航栏与Navigation控制器绑定，导致菜单点击事件没有被Navigation组件处理。

修改MainActivity代码，添加导航控制器与底部导航栏的关联代码：

class MainActivity : AppCompatActivity() {

    private lateinit var binding : ActivityMainBinding
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)
        val navHostFragment = supportFragmentManager
            .findFragmentById(R.id.fragmentContainerView)  as NavHostFragment
        val navController = navHostFragment.navController
        
        // 新增：绑定底部导航栏与导航控制器
        NavigationUI.setupWithNavController(binding.bottomNav, navController)
    }
}

注意：需确保ActivityMainBinding中的底部导航栏控件id为bottomNav（对应布局文件中BottomNavigationView的android:id="@+id/bottomNav"），如果你的控件id不同，替换为实际id即可。

验证：重新运行应用，点击底部菜单即可正常切换到saveFragment页面。

内容的提问来源于stack exchange，提问作者Nazir