title: Resource id cannot be an empty string
body: <p>I am an absolutely beginner in Android coding. In Messages Gradle Build, I got error:</p>
  
  <blockquote>
    <p>Resource id cannot be an empty string (as 'id' with value '@+id/').</p>
  </blockquote>
  
  <p>The highlighted string is:</p>
  
  <pre><code>android:id="@+id/"&gt;
  </code></pre>
  
  <p>However, the string seems to created automatically by Android Studio.
  Anything I am missing?</p>