title: Android layout error: no resource identifier found for attribute 'lineWidth' in package
body: <p>I already import <a href="https://github.com/JakeWharton/Android-ViewPagerIndicator" rel="nofollow">viewpagerindicator</a>, but when I make the project, the complier show the error.
  The error message is :  error: No resource identifier found for attribute 'lineWidth' in package 'com.example.sample'
  My use IDE is Intellij.
  How can I fix this problem?
  Thanks.</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto"
      android:layout_width="match_parent"
      android:layout_height="match_parent"&gt;
  
      &lt;com.viewpagerindicator.LinePageIndicator
          android:id="@+id/indicator"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"
          android:layout_alignParentBottom="true"
          android:layout_marginBottom="3dp"
          app:lineWidth="25dp" /&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>