title: Android find default background color
body: <p>I have an app with a simple recyclerview.</p>
  
  <p>The layout is declared as follow</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="match_parent"
      android:layout_height="match_parent"&gt;
  
  
      &lt;android.support.v7.widget.RecyclerView
          android:id="@+id/contentView"
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:layout_above="@+id/some_id" /&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p>I notice that on different devices, the recyclerView actually had a different background. In newer devices, the background is just white. On older devices, the background is light gray.</p>
  
  <p>In android studio, the background color is blank in the design view. </p>
  
  <p>So my question is, where does this gray color come from? How can I change it universally to white?</p>
  
  <p>I can obviously just add background:white to this particular view. But is there a way to overwrite the system default?</p>