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android - NavController 不会将片段更改为新目的地

问题描述

问题： Fragment 未更改为下一个 Fragment
条件：使用 BottomNavigationView、Navigation 组件和多模块 app
操作：

  1. 在模拟器上启动应用程序
  2. 启动应用程序时，将显示主页片段
  3. 当点击消息图标或我的页面图标时，片段不会改变

我的检查： 在 NavController.java 中点击 ic on 更改片段时，我调试了应用程序

        NavDestination newDest = navigator.navigate(node, finalArgs,
                navOptions, navigatorExtras);

返回预期的片段，但片段不会改变......

项目结构：

代码：
activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
    <androidx.constraintlayout.widget.ConstraintLayout
        android:id="@+id/container">

        <com.google.android.material.bottomnavigation.BottomNavigationView
            android:id="@+id/nav_view"
            app:menu="@menu/bottom_nav_menu" />

        <androidx.fragment.app.FragmentContainerView
            android:id="@+id/nav_host_fragment"
            android:name="androidx.navigation.fragment.NavHostFragment"
            app:defaultNavHost="true"
            app:navGraph="@navigation/navigation" />

    </androidx.constraintlayout.widget.ConstraintLayout>
</layout>

bottom_nav_menu.xml

<menu xmlns:android="http://schemas.android.com/apk/res/android">

    <item
        android:id="@+id/navigation_home"
        android:icon="@drawable/ic_dashboard_black_24dp"
        android:title="@string/title_home"
        android:enabled="true"/>

    <item
        android:id="@+id/navigation_message"
        android:icon="@drawable/ic_notifications_black_24dp"
        android:title="@string/title_message"
        android:enabled="true"/>

    <item
        android:id="@+id/navigation_mypage"
        android:icon="@drawable/ic_notifications_black_24dp"
        android:title="@string/title_mypage"
        android:enabled="true" />
</menu>

导航.xml

<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/navigation"
    app:startDestination="@+id/navigation_home">

    <fragment
        android:id="@+id/navigation_home"
        android:name="app.home.HomeFragment"
        android:label="@string/title_home" />

    <fragment
        android:id="@+id/navigation_message"
        android:name="app.message.MessageFragment"
        android:label="@string/title_message"/>

    <fragment
        android:id="@+id/navigation_mypage"
        android:name="app.mypage.MyPageFragment"
        android:label="@string/title_mypage" />

</navigation>

MainActivity.kt

class MainActivity : AppCompatActivity() {
    private val binding: ActivityMainBinding by lazy {
        DataBindingUtil.setContentView<ActivityMainBinding>(
            this,
            R.layout.activity_main
        )
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        val navView: BottomNavigationView = binding.navView
        val navHostFragment =  supportFragmentManager.findFragmentById(R.id.nav_host_fragment)  as NavHostFragment
        navView.setupWithNavController(navHostFragment.navController)
        navView.setOnNavigationItemSelectedListener { item:MenuItem ->
            Log.d("main", "setOnNavigationItemSelectedListener " + item)
            navHostFragment.navController.navigate(item.itemId)
            true
        }
    }

构建.gradle（应用程序）

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
apply plugin: 'kotlin-kapt'
apply plugin: "androidx.navigation.safeargs"

android {
    compileSdkVersion 29
    buildToolsVersion "29.0.3"
    repositories {
        google()
    }

    defaultConfig {
        applicationId "app"
        minSdkVersion 26
        targetSdkVersion 29
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"

        flavorDimensions "default"
        productFlavors {
            develop {
                applicationIdSuffix ".develop"
            }
            staging {
                applicationIdSuffix ".staging"
            }
        }
    }

    buildTypes {
        release {
            minifyEnabled false
            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{
        dataBinding = true
    }
}

dependencies {
    implementation fileTree(dir: "libs", include: ["*.jar"])
    //
    implementation project(":core")
    implementation project(":features:home")
    implementation project(":features:message")
    implementation project(":features:mypage")
    //
    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    implementation 'androidx.core:core-ktx:1.3.0'
    implementation 'androidx.appcompat:appcompat:1.1.0'
    implementation 'com.google.android.material:material:1.1.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'androidx.navigation:navigation-fragment:2.2.2'
    implementation 'androidx.navigation:navigation-ui:2.2.2'
    implementation 'androidx.lifecycle:lifecycle-extensions:2.2.0'
    implementation 'androidx.navigation:navigation-fragment-ktx:2.2.2'
    implementation 'androidx.navigation:navigation-ui-ktx:2.2.2'
    implementation 'androidx.legacy:legacy-support-v4:1.0.0'
    implementation 'androidx.recyclerview:recyclerview:1.1.0'
    implementation 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.2.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'

}

当我尝试从 Android Studio 模板的 BottomNavigationView 创建活动时，它运行良好。但是我尝试将其拆分为多模块应用程序，但效果不佳。

有什么建议吗？？

标签： androidandroid-fragmentsandroid-navigationandroid-bottomnavigationview

解决方案

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