title: FirebaseUI causes DexException Multiple Dex Files
body: <p>I am using FirebaseUI to try out the RecyclerViewAdapter. When I try to run the app the gradle build doesn't succeed and gives these errors:
  <a href="https://i.stack.imgur.com/Yaxak.png" rel="nofollow noreferrer">Errors shown by Gradle</a></p>
  
  <p>This doesn't happen when I take out the FirebaseUI Dependency.</p>
  
  <pre><code>dependencies {
  implementation fileTree(dir: 'libs', include: ['*.jar'])
  implementation "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
  implementation 'com.android.support:appcompat-v7:27.1.1'
  implementation 'com.firebaseui:firebase-ui-database:4.1.0'
  implementation 'com.android.support:design:27.1.1'
  implementation 'com.android.support:cardview-v7:27.1.1'
  implementation 'com.android.support:recyclerview-v7:27.1.1'
  implementation 'com.android.support.constraint:constraint-layout:1.1.2'
  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'}
  </code></pre>
  
  <p>Edit: I added MultiDex Support as mentioned on <a href="https://developer.android.com/studio/build/multidex#mdex-gradle" rel="nofollow noreferrer">Android Developers Site</a></p>
  
  <p>What should I do to make the build successful and run the app.</p>
  
  <p>Thanks in advance.</p>