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我正在开发 android 应用程序并且我使用了 MaterialCardView 但我得到了以下异常

the following classes could not be instantiated:
- com.google.android.material.card.MaterialCardView (Open Class, Show Exception, Clear Cache)
 Tip: Use View.isInEditMode() in your custom views to skip code or show sample data when shown in the IDE.  If this is an unexpected error you can also try to build the project, then manually refresh the layout.  Exception Details java.lang.ClassNotFoundException: com.google.android.material.R$attr   at java.lang.ClassLoader.loadClass(ClassLoader.java:419)   at java.lang.ClassLoader.loadClass(ClassLoader.java:352)   at com.google.android.material.card.MaterialCardView.<clinit>   ... (MaterialCardView.java:90)   at java.lang.reflect.Constructor.newInstance(Constructor.java:423)   at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:961)   at android.view.LayoutInflater.inflate(LayoutInflater.java:659)   at android.view.LayoutInflater.inflate(LayoutInflater.java:501) Copy stack to clipboard

在我使用 MaterialCardView 的 xml 文件下方

<?xml version="1.0" encoding="utf-8"?>
    <com.google.android.material.card.MaterialCardView 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:layout_width="wrap_content"
        android:layout_height="wrap_content">
    
        <androidx.constraintlayout.widget.ConstraintLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="10dp">
    
            <androidx.appcompat.widget.AppCompatImageView
                android:id="@+id/ivUser"
                android:layout_width="100dp"
                android:layout_height="100dp"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintLeft_toLeftOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                tools:srcCompat="@tools:sample/avatars" />
    
            <androidx.appcompat.widget.AppCompatTextView
                android:id="@+id/tvName"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginStart="10dp"
                android:textColor="@color/black"
                android:textSize="20sp"
                app:layout_constraintStart_toEndOf="@+id/ivUser"
                app:layout_constraintTop_toTopOf="parent"
                tools:text="TextView"
                android:layout_marginLeft="10dp" />
    
            <androidx.appcompat.widget.AppCompatTextView
                android:id="@+id/tvAddress"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="5dp"
                android:textColor="@color/black"
                android:textSize="15sp"
                app:layout_constraintStart_toStartOf="@+id/tvName"
                app:layout_constraintTop_toBottomOf="@+id/tvName"
                tools:text="TextView" />
    
        </androidx.constraintlayout.widget.ConstraintLayout>
    </com.google.android.material.card.MaterialCardView>

在我的 app.gradle 下面

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
apply plugin: 'kotlin-kapt'
apply plugin: 'dagger.hilt.android.plugin'



android {
    compileSdkVersion 30
    buildToolsVersion "30.0.2"

    defaultConfig {
        applicationId "yodgorbekkomilov.edgar.printfultask"
        minSdkVersion 15
        targetSdkVersion 30
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
}

dependencies {
    implementation fileTree(dir: "libs", include: ["*.jar"])
    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    implementation 'androidx.core:core-ktx:1.3.2'
    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.0.3'
    implementation "io.ktor:ktor-client-android:1.4.0"
    implementation "io.ktor:ktor-network:1.4.0"
    implementation 'com.google.android.gms:play-services-maps:17.0.0'
    implementation "com.google.dagger:hilt-android:2.28-alpha"
    implementation "androidx.hilt:hilt-lifecycle-viewmodel:1.0.0-alpha02"
    kapt "com.google.dagger:hilt-android-compiler:2.28-alpha"

    implementation 'com.google.android.material:material:1.2.1'

    implementation 'com.github.bumptech.glide:glide:4.11.0'
    annotationProcessor 'com.github.bumptech.glide:compiler:4.11.0'
    def lifecycle_version = "2.2.0"
    def arch_version = "2.1.0"

    // ViewModel
    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:$lifecycle_version"
    // LiveData
    implementation "androidx.lifecycle:lifecycle-livedata-ktx:$lifecycle_version"
    // Lifecycles only (without ViewModel or LiveData)
    implementation "androidx.lifecycle:lifecycle-runtime-ktx:$lifecycle_version"
    implementation 'androidx.fragment:fragment-ktx:1.1.0'
    // Saved state module for ViewModel
    implementation "androidx.lifecycle:lifecycle-viewmodel-savedstate:$lifecycle_version"

    // Annotation processor
    kapt "androidx.lifecycle:lifecycle-compiler:$lifecycle_version"
    // alternately - if using Java8, use the following instead of lifecycle-compiler
    implementation "androidx.lifecycle:lifecycle-common-java8:$lifecycle_version"

    // optional - helpers for implementing LifecycleOwner in a Service
    implementation "androidx.lifecycle:lifecycle-service:$lifecycle_version"

    // optional - ProcessLifecycleOwner provides a lifecycle for the whole application process
    implementation "androidx.lifecycle:lifecycle-process:$lifecycle_version"


    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'

}

在我的夜晚/themes.xml 下面

<resources xmlns:tools="http://schemas.android.com/tools">
    <!-- Base application theme. -->
    <style name="Theme.PrintfulApp" parent="Theme.MaterialComponents.DayNight.NoActionBar">
        <!-- Primary brand color. -->
        <item name="colorPrimary">@color/purple_200</item>
        <item name="colorPrimaryVariant">@color/purple_700</item>
        <item name="colorOnPrimary">@color/black</item>
        <!-- Secondary brand color. -->
        <item name="colorSecondary">@color/teal_200</item>
        <item name="colorSecondaryVariant">@color/teal_200</item>
        <item name="colorOnSecondary">@color/black</item>
        <!-- Status bar color. -->
        <item name="android:statusBarColor" tools:targetApi="l">?attr/colorPrimaryVariant</item>
        <!-- Customize your theme here. -->
    </style>
</resources>

低于值/themes.xml

<resources xmlns:tools="http://schemas.android.com/tools">
    <!-- Base application theme. -->
    <style name="Theme.PrintfulApp" parent="Theme.MaterialComponents.DayNight.NoActionBar">
        <!-- Primary brand color. -->
        <item name="colorPrimary">@color/purple_500</item>
        <item name="colorPrimaryVariant">@color/purple_700</item>
        <item name="colorOnPrimary">@color/white</item>
        <!-- Secondary brand color. -->
        <item name="colorSecondary">@color/teal_200</item>
        <item name="colorSecondaryVariant">@color/teal_700</item>
        <item name="colorOnSecondary">@color/black</item>
        <!-- Status bar color. -->
        <item name="android:statusBarColor" tools:targetApi="l">?attr/colorPrimaryVariant</item>
        <!-- Customize your theme here. -->
    </style>
</resources>

我想知道我在哪里犯了错误

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