无法解决：com.google.firebase：firebase-core：16.0.1

Question

我正在尝试将Firebase云存储添加到我的应用程序。以下是应用程序build.gradle。但是它说：无法解决：com.google.firebase：firebase-core：16.0.1。为什么？依赖项中根本没有firebase-core。apply plugin: 'com.android.application'android {    compileSdkVersion 27    defaultConfig {        applicationId "com.louise.udacity.mydict"        minSdkVersion 15        targetSdkVersion 27        versionCode 1        versionName "1.0"        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"    }    buildTypes {        release {            minifyEnabled false            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'        }    }}dependencies {    implementation fileTree(dir: 'libs', include: ['*.jar'])    implementation 'com.android.support:appcompat-v7:27.1.1'    implementation 'com.android.support.constraint:constraint-layout:1.1.0'    implementation 'com.google.firebase:firebase-storage:16.0.1'    implementation 'com.google.firebase:firebase-auth:16.0.1'    testImplementation 'junit:junit:4.12'    androidTestImplementation 'com.android.support.test:runner:1.0.2'    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'    implementation 'com.google.cloud:google-cloud-storage:1.31.0'    implementation 'com.firebase:firebase-jobdispatcher:0.8.5'}apply plugin: 'com.google.gms.google-services'