firebaseCM/fcm/app/build.gradle

plugins {
    id 'com.android.application'
    id 'com.google.gms.google-services'
}

android {
    compileSdkVersion 29
    buildToolsVersion "29.0.3"

    defaultConfig {
        applicationId "com.example.fcm"
        minSdkVersion 16
        targetSdkVersion 29
        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
    }

    viewBinding {
        enabled = true
    }
}

dependencies {

    implementation 'androidx.appcompat:appcompat:1.1.0'
    implementation 'com.google.android.material:material:1.1.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'com.google.firebase:firebase-messaging:20.2.0'
    implementation 'android.arch.work:work-runtime:2.0.1-rc01'
    implementation 'com.google.firebase:firebase-database:19.3.0'
    implementation 'com.firebase:firebase-client-android:2.5.0'
    implementation 'com.android.volley:volley:1.1.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
}

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