title: Style's CardBackgroundColor not working on CardView
body: <p>I can't work out why my CardView doesn't get the background color set by my style. According to this answer on another StackOverflow question <a href="https://stackoverflow.com/a/58270201/9275661">here</a> using the old AndroidSupport-library you should just be able to set it by adding this to the default AppTheme:</p>
  <pre class="lang-xml prettyprint-override"><code>&lt;item name=&quot;cardBackgroundColor&quot;&gt;#ff00ab&lt;/item&gt;
  </code></pre>
  <p>However, this doesn't change the color in any way for me. Normally setting the color through <code>app:cardBackgroundColor=&quot;...&quot;</code> works fine, but for my application I need it to work through the styles.</p>
  <p>I also tested it using a new project and just adding the minimal steps to make it work, but it still doesn't have the card color set by the style...</p>
  <p>Here is my <code>activity_main.xml</code>:</p>
  <pre class="lang-xml prettyprint-override"><code>&lt;RelativeLayout xmlns:android=&quot;http://schemas.android.com/apk/res/android&quot;
      xmlns:app=&quot;http://schemas.android.com/apk/res-auto&quot;
      android:id=&quot;@+id/activity_main&quot;
      android:orientation=&quot;vertical&quot;
      android:layout_width=&quot;match_parent&quot;
      android:layout_height=&quot;match_parent&quot;&gt;
  
      &lt;androidx.cardview.widget.CardView
          android:layout_width=&quot;match_parent&quot;
          android:layout_height=&quot;match_parent&quot;&gt;
  
          &lt;TextView
              android:layout_width=&quot;match_parent&quot;
              android:layout_height=&quot;match_parent&quot;
              android:text=&quot;testing string&quot;/&gt;
  
      &lt;/androidx.cardview.widget.CardView&gt;
  &lt;/RelativeLayout&gt;
  </code></pre>
  <p>In my <code>styles.xml</code> I've added the simple line above to the default Base application theme.</p>
  <p>Thanks for any help solving my problem!</p>
  <p><em>EDIT</em>:
  The AppTheme is just the default AppTheme with the line added above. It finally looks like this:</p>
  <pre class="lang-xml prettyprint-override"><code>&lt;style name=&quot;AppTheme&quot; parent=&quot;Theme.AppCompat.Light.DarkActionBar&quot;&gt;
      &lt;!-- Customize your theme here. --&gt;
      &lt;item name=&quot;colorPrimary&quot;&gt;@color/colorPrimary&lt;/item&gt;
      &lt;item name=&quot;colorPrimaryDark&quot;&gt;@color/colorPrimaryDark&lt;/item&gt;
      &lt;item name=&quot;colorAccent&quot;&gt;@color/colorAccent&lt;/item&gt;
      &lt;item name=&quot;cardBackgroundColor&quot;&gt;#ff00ab&lt;/item&gt;
  &lt;/style&gt;
  </code></pre>