Android Studio - Unresolved Reference errors for Kotlin coroutines but code compiles

Question

today I started to experience some weird behavior in Android Studio 2020.3.1. I get Unresolved Reference errors for all methods from Kotlin coroutines. I cannot narrow down this issue to any specific change I made. The code still compiles and my App works fine. The only change that might be connected to this issue is that I created a new git branch a day before (everything worked fine though).

Text

My build.gradle file looks like this:

apply plugin: 'com.android.application'

apply plugin: 'kotlin-android'

apply plugin: 'kotlin-kapt'

apply plugin: 'com.google.gms.google-services'

apply plugin: 'com.google.firebase.crashlytics'

android {
    compileSdkVersion 31
    defaultConfig {
        minSdkVersion 24
        targetSdkVersion 31
        versionCode 13
        versionName "1.5.4"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
        kapt {
            arguments {
                arg("room.schemaLocation", "$projectDir/schemas".toString())
            }
        }
        kotlinOptions {
            jvmTarget = '1.8'
        }
        compileOptions {
            targetCompatibility = "8"
            sourceCompatibility = "8"
        }
    }

    buildFeatures {
        viewBinding true
    }


    packagingOptions {
        exclude 'META-INF/atomicfu.kotlin_module'
    }

    sourceSets { main { java.srcDirs = ['src/main/java', 'src/main/java/utilities'] } }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation "org.jetbrains.kotlin:kotlin-reflect:1.5.31"
    implementation 'androidx.appcompat:appcompat:1.3.1'
    implementation 'androidx.core:core-ktx:1.7.0'
    implementation 'androidx.legacy:legacy-support-v4:1.0.0'
    implementation 'com.google.android.material:material:1.5.0-alpha05'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.1'
    implementation 'androidx.preference:preference-ktx:1.1.1'
    implementation 'androidx.recyclerview:recyclerview:1.2.1'
    implementation "androidx.viewpager2:viewpager2:1.0.0"
    testImplementation 'junit:junit:4.13.1'
    androidTestImplementation 'androidx.test.ext:junit:1.1.3'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'

    // Logcat
    implementation 'com.squareup.logcat:logcat:0.1'

    // Room components (SQL Wrapper)
    implementation "androidx.room:room-runtime:$rootProject.roomVersion"
    implementation "androidx.room:room-ktx:$rootProject.roomVersion"
    implementation "androidx.room:room-rxjava3:$rootProject.roomVersion"
    kapt "androidx.room:room-compiler:$rootProject.roomVersion"
    androidTestImplementation "androidx.room:room-testing:$rootProject.roomVersion"

    // Paging
    implementation "androidx.paging:paging-runtime-ktx:$rootProject.pagingVersion"
    implementation "androidx.paging:paging-rxjava2-ktx:$rootProject.pagingVersion"

    // Fragment
    implementation "androidx.fragment:fragment-ktx:$fragment_version"

    // Lifecycle components
    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:$lifecycle_version" // ViewModel
    implementation "androidx.lifecycle:lifecycle-livedata-ktx:$lifecycle_version" // LiveData
    implementation "androidx.lifecycle:lifecycle-runtime-ktx:$lifecycle_version" // Lifecycles only (without ViewModel or LiveData)
    implementation "androidx.lifecycle:lifecycle-viewmodel-savedstate:$lifecycle_version" // Saved state module for ViewModel
    implementation "androidx.lifecycle:lifecycle-common-java8:$lifecycle_version" // Annotation processor"
    implementation "androidx.lifecycle:lifecycle-service:$lifecycle_version" // optional - helpers for implementing LifecycleOwner in a Service
    implementation "androidx.lifecycle:lifecycle-process:$lifecycle_version" // optional - ProcessLifecycleOwner provides a lifecycle for the whole application process
    implementation "androidx.lifecycle:lifecycle-reactivestreams-ktx:$lifecycle_version" // optional - ReactiveStreams support for LiveData
    testImplementation "androidx.arch.core:core-testing:$arch_version" // optional - Test helpers for LiveData

    // RxJava
    implementation 'io.reactivex.rxjava3:rxandroid:3.0.0'
    implementation 'io.reactivex.rxjava3:rxjava:3.0.2'
    implementation 'io.reactivex.rxjava3:rxkotlin:3.0.0'

    // ViewModel Kotlin support
    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:$rootProject.archLifecycleVersion"

    // Coroutines
    // api "org.jetbrains.kotlinx:kotlinx-coroutines-core:$rootProject.coroutines"
    // api "org.jetbrains.kotlinx:kotlinx-coroutines-android:$rootProject.coroutines"
    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.5.0'
    implementation 'androidx.core:core-ktx:1.7.0'

    // Location
    implementation 'com.google.android.gms:play-services-location:18.0.0'

    // Apache common math
    implementation 'org.apache.commons:commons-math3:3.6.1'


    // CameraX core library using the camera2 implementation
    // The following line is optional, as the core library is included indirectly by camera-camera2
    implementation("androidx.camera:camera-core:$rootProject.camerax_version")
    implementation("androidx.camera:camera-camera2:$rootProject.camerax_version")
    // If you want to additionally use the CameraX Lifecycle library
    implementation("androidx.camera:camera-lifecycle:$rootProject.camerax_version")
    // If you want to additionally use the CameraX View class
    implementation("androidx.camera:camera-view:1.0.0-alpha30")
    // If you want to additionally use the CameraX Extensions library
    implementation("androidx.camera:camera-extensions:1.0.0-alpha30")

    // FireBase
    implementation platform('com.google.firebase:firebase-bom:28.4.0')
    implementation 'com.google.firebase:firebase-analytics-ktx'
    implementation 'com.google.firebase:firebase-crashlytics-ktx'
}

buildscript {
    ext.kotlin_version = '1.5.31'
    repositories {
        google()
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:7.0.3'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
        classpath 'com.google.gms:google-services:4.3.10'
        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.7.1'
    }
}

allprojects {
    repositories {
        google()
        mavenCentral()
        maven { url "https://jitpack.io" }
    }
}

ext {
    roomVersion = '2.3.0'
    pagingVersion = '3.0.1'
    archLifecycleVersion = '2.2.0'
    androidxArchVersion = '2.0.0'
    coroutines = '1.2.0'
    lifecycle_version = '2.4.0'
    arch_version = '2.1.0'
    fragment_version = '1.3.6'
    camerax_version = "1.0.2"
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

Things I have tried to resolve this:

Invalidated caches and restarted Android Studio
Sync gradle files again
Deleted .idea and .gradle folders
Switched to another git branch that worked fine before and where no changes were made
Restarted my PC

Now I am out of ideas of what to try. If anyone has an idea what the issue could be, I would be really grateful.

Edit: If I edit kotlinx implementation in the build.gradle file to:

    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.5.2-native-mt'

the errors disappear, however, I do not understand why.

Android Studio - Unresolved Reference errors for Kotlin coroutines but code compiles

0 Answers