Android 未解析的引用：视图模型

我正在try 创建一个ViewModel，但我遇到了一个未解析的引用问题:viewModel

这是ViewModel的一个实现

    private val mainVm by viewModels<MainViewModel>()

MainViewModel.kt

package com.example.aplikacjazporadnika

import androidx.lifecycle.ViewModel

class MainViewModel: ViewModel() {
    var clicker: Int = 0
}

Build.gradle(模块:APP)

dependencies {

    def activity_version = "1.7.2"
    // Kotlin
    implementation "androidx.activity:activity-ktx:$activity_version"

    def fragment_version = "1.6.1"
    // Kotlin
    implementation "androidx.fragment:fragment-ktx:$fragment_version"

    implementation 'androidx.core:core-ktx:1.9.0'
    implementation 'androidx.appcompat:appcompat:1.6.1'
    implementation 'com.google.android.material:material:1.9.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.5'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
}```




I tried to add various implementations that I found in other sites but none of there actually worked