java - 未知片段 & 无法启动一个或多个类

Question

所以我得到了这些错误：

这是我的 xml 文件：

    <?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.widget.DrawerLayout
    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/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    android:background="@drawable/background"
    tools:openDrawer="start">

<com.google.android.material.navigation.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        android:background="@color/overlayBAckground"
        app:itemTextColor="@android:color/white"
        app:itemIconTint="@android:color/white"
        app:headerLayout="@layout/nav_header_home"
        app:menu="@menu/activity_home_drawer" />

        <include
        layout="@layout/app_bar_home"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</androidx.drawerlayout.widget.DrawerLayout>

在 gradle 依赖项中，我有这个：

implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.0.2'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'com.google.firebase:firebase-core:17.1.0'
    implementation 'com.google.firebase:firebase-database:19.0.0'
    implementation 'androidx.legacy:legacy-support-v4:1.0.0'
    implementation 'com.google.android.material:material:1.0.0'
    implementation 'androidx.navigation:navigation-fragment:2.0.0'
    implementation 'androidx.navigation:navigation-ui:2.0.0'
    implementation 'androidx.lifecycle:lifecycle-extensions:2.0.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test:runner:1.2.0'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
    implementation 'androidx.recyclerview:recyclerview:1.0.0'
    implementation 'com.squareup.picasso:picasso:2.71828'
    implementation 'androidx.cardview:cardview:1.0.0'
    implementation 'com.firebaseui:firebase-ui-database:1.2.0'
    def nav_version = "2.1.0-alpha01"
    implementation "androidx.navigation:navigation-fragment:$nav_version"
    implementation "androidx.navigation:navigation-ui:$nav_version"

如果您需要更多信息，请在下方评论。我看过其他帖子，但没有一个解决方案也对我有用。也许我看的不够深入，但是如果您知道出了什么问题，请帮助我。

标签： javaandroidandroid-studio