ViewModelProviders.of(activity) 只接受片段或片段活动

Question

i have a problem using mvvm in splash activity and relate the viewmodel to the activity,i don't won't to create fragment for it . in AppCompatActivity:

fun <T : ViewModel> AppCompatActivity.obtainViewModel(viewModelClass: Class<T>) =
    ViewModelProviders.of(this, ViewModelFactory.getInstance(application)).get(viewModelClass)

it says that .of(this,factor) only accept fragment and fragmentActivity i already read link but it doesn't solve the problem my build.grable:

apply plugin: 'com.android.application'

apply plugin: 'kotlin-android'
apply plugin: 'kotlin-kapt'

apply plugin: 'kotlin-android-extensions'

android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.attendance.myproject.begory"
        minSdkVersion 21
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

    // to prevent the addition of jvm-target
    kotlinOptions {
        jvmTarget = JavaVersion.VERSION_1_8.toString()
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
    buildFeatures {
        dataBinding true
    }
}

dependencies {
    def room_version = "2.2.3" // check latest version from docs

    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.4.10"
    implementation "androidx.recyclerview:recyclerview:$rootProject.recyclerViewVersion"
    implementation "androidx.cardview:cardview:$rootProject.cardViewVersion"
    implementation "androidx.constraintlayout:constraintlayout:2.0.2"
    //noinspection GradleCompatible

    implementation 'androidx.appcompat:appcompat:1.3.0-alpha02'
//room

    implementation "androidx.room:room-runtime:$room_version"
    kapt "androidx.room:room-compiler:$room_version"

    implementation "com.google.android.material:material:1.3.0-alpha03"
    implementation 'androidx.navigation:navigation-fragment-ktx:2.3.1'
    implementation 'androidx.navigation:navigation-ui-ktx:2.3.1'
    testImplementation 'junit:junit:4.13'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
    implementation 'com.google.firebase:firebase-core:17.5.1'
    implementation 'com.google.firebase:firebase-auth:19.4.0'
    implementation 'com.google.firebase:firebase-database:19.5.1'
    implementation 'com.firebase:firebase-client-android:2.3.1'
    implementation 'com.google.code.gson:gson:2.8.5'
    implementation 'me.dm7.barcodescanner:zxing:1.9.8'

    //    Add Zxing library to generate barcode
    implementation 'com.google.zxing:core:3.2.1'
    implementation 'com.journeyapps:zxing-android-embedded:3.2.0@aar'
    implementation "org.jetbrains.kotlin:kotlin-script-runtime:1.4.10"
    //curved bottom navigation
    implementation 'np.com.susanthapa.curved_bottom_navigation:curved_bottom_navigation:0.6.3'

    implementation "androidx.lifecycle:lifecycle-extensions:$archLifecycleVersion"
    kapt "androidx.lifecycle:lifecycle-compiler:$archLifecycleVersion"
    implementation "androidx.core:core-ktx:1.3.2"
    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:2.2.0"
    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.9'
    implementation'android.arch.lifecycle:extensions:1.1.1'
}
apply plugin: 'com.google.gms.google-services'

I'm using androidx and the activity is extended from the appcompatActivitty .I had initiate the viewmodel in the on create fun .

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_splash)
    if(!Internet.isOnline(applicationContext)) showMessage(getString(R.string.no_internet_connection))

    binding= DataBindingUtil.setContentView(this, R.layout.activity_splash)
    splashViewModel = obtainViewModel()
    binding.splashViewModel
    subscribeToNavigationChanges(splashViewModel)

}

I really takes days searching in this problem if any one can help it will be very thankful.

Answer 1

The problem is that you're using the wrong ViewModelProviders import. You need to remove this line from your dependencies:

implementation 'android.arch.lifecycle:extensions:1.1.1'

android.arch.lifecycle is the old, pre-AndroidX artifacts that you should not and cannot use when using AndroidX dependencies. You already have the androidx.lifecycle:lifecycle-extensions dependency, which is the full replacement for android.arch.lifecycle:extensions , which actually has the right version of ViewModelProviders that works with the AndroidX version of AppCompatActivity .

Note that there's no reason to write or use any method like your obtainViewModel since this is already provided for you by val viewModel: YourViewModel by viewModels() that is part of the activity-ktx dependency (that you already get as a transitive dependency through navigation-fragment-ktx .