title: App crashed after adding flutter firebase auth ui
body: <p>Flutter firebase auth UI have some issue, because of firebase_auth version miss match issue </p>
  
  <p>My flutter app crashed and unable to identify an issue, after opening in an android studio, I got the issue and it is here </p>
  
  <pre><code>Caused by: java.lang.IllegalStateException: Default FirebaseApp is not initialized in this process com.mycom.mypetshop. Make sure to call FirebaseApp.initializeApp(Context) first.
          at com.google.firebase.FirebaseApp.getInstance(com.google.firebase:firebase-common@@16.0.2:240)
          at com.google.firebase.auth.FirebaseAuth.getInstance(Unknown Source)
          at io.flutter.plugins.firebaseauth.FirebaseAuthPlugin.&lt;init&gt;(FirebaseAuthPlugin.java:54)
          at io.flutter.plugins.firebaseauth.FirebaseAuthPlugin.registerWith(FirebaseAuthPlugin.java:47)
          at io.flutter.plugins.GeneratedPluginRegistrant.registerWith(GeneratedPluginRegistrant.java:20)
          at com.vyapari2online.mypetshop.MainActivity.onCreate(MainActivity.java:11)
          at android.app.Activity.performCreate(Activity.java:5990)
  </code></pre>
  
  <p>How to solve this?</p>
  
  <blockquote>
    <p>In project 'app' a resolved Google Play services library dependency
    depends on another at an exact version (e.g. "[15.0. 1]", but isn't
    being resolved to that version. Behavior exhibited by the library will
    be unknown.</p>
    
    <p>Dependency failing: com.google.android.gms:play-services-flags:15.0.1
    -> com.google.android.gms:play-services-basement@[
    15.0.1], but play-services-basement version was 16.0.1.</p>
    
    <p>The following dependencies are project dependencies that are direct or
    have transitive dependencies that lead to the art ifact with the
    issue.
    -- Project 'app' depends on project 'firebase_auth' which depends onto com.google.firebase:firebase-auth@16.0.2
    -- Project 'app' depends on project 'firebase_core' which depends onto com.google.firebase:firebase-core@16.0.4
    -- Project 'app' depends on project 'cloud_firestore' which depends onto com.google.firebase:firebase-firestore@17.1.1
    -- Project 'app' depends on project 'google_sign_in' which depends onto com.google.android.gms:play-services-auth@16.0.1</p>
    
    <p>For extended debugging info execute Gradle from the command line with
    ./gradlew --info :app:assembleDebug to see the dep endency paths to
    the artifact. This error message came from the google-services Gradle
    plugin, report issues at https://
    github.com/google/play-services-plugins and disable by adding
    "googleServices { disableVersionCheck = false }" to your b uild.gradle
    file.</p>
  </blockquote>
  
  <p>#flutter_firebase_ui have a lot of issues #google please hire me, I can help your developers </p>