Quiero usar componentes de arquitectura de navegación.

Pero tengo un problema con la importación de safeargs

Mensaje de sincronización:

No se pudo encontrar androidx.navigation: safe-args-gradle-plugin: 1.0.0-alpha01. Buscado en las siguientes ubicaciones:
https: //dl.google.com/dl/android/maven2/androidx/navigation/safe-args-gradle-plugin/1.0.0-alpha01/safe-args-gradle-plugin-1.0.0-alpha01.pom @
https: //dl.google.com/dl/android/maven2/androidx/navigation/safe-args-gradle-plugin/1.0.0-alpha01/safe-args-gradle-plugin-1.0.0-alpha01.jar @
https: //jcenter.bintray.com/androidx/navigation/safe-args-gradle-plugin/1.0.0-alpha01/safe-args-gradle-plugin-1.0.0-alpha01.po
https: //jcenter.bintray.com/androidx/navigation/safe-args-gradle-plugin/1.0.0-alpha01/safe-args-gradle-plugin-1.0.0-alpha01.ja
Requerido por
proyecto:

SeguíAgregando Componentes a su Proyecto pero no resolvió mi problema.

Project: build.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {

    repositories {
        google()
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.2'
        classpath "androidx.navigation:safe-args-gradle-plugin:1.0.0-alpha01"

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
    }
}

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

Module: build.gradle

apply plugin: 'com.android.application'
apply plugin: 'androidx.navigation.safeargs'

android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "com.mangoslab.navigation"
        minSdkVersion 21
        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'
    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'

    def nav_version = "1.0.0-alpha01"

    implementation "android.arch.navigation:navigation-fragment:${nav_version}" // use -ktx for Kotlin
    implementation "android.arch.navigation:navigation-ui:${nav_version}" // use -ktx for Kotlin

    // optional - Test helpers
    androidTestImplementation "android.arch.navigation:navigation-testing:${nav_version}" // use -ktx for Kotlin
}