title: How to use "match_parent" with Xamarin Forms' "VerticalOptions="FillAndExpand""?
body: <p>I use WebView in Xamarin Forms like this:</p>
  
  <pre><code>    &lt;ContentPage.Content&gt;
          &lt;local:HybridWebView x:Name="hybridWebView" Uri="https://code4nara.github.io/Maplat/?appid=jizoapp&amp;amp;overlay=true" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand" /&gt;
      &lt;/ContentPage.Content&gt;
  </code></pre>
  
  <p>But in side of this webview, height of http body shrinks to 0, so css "<strong>height:100%</strong>" or so not works.
  I searched about thi issue, This article is found.
  <a href="https://stackoverflow.com/questions/39049071/android-webview-how-to-let-the-css-use-the-entire-height-w-position-absolute/39111065">Android WebView: how to let the css use the entire height w/ position absolute?</a>
  It says,</p>
  
  <pre><code>android:layout_alignParentBottom="true"
  android:layout_alignParentRight="true"
  android:layout_alignParentEnd="true"
  android:layout_alignParentTop="true"
  android:layout_alignParentLeft="true"
  android:layout_alignParentStart="true"
  </code></pre>
  
  <p>causes webview body's height 0px.</p>
  
  <pre><code>android:layout_width="match_parent"
  android:layout_height="match_parent"
  </code></pre>
  
  <p>works well.</p>
  
  <p>So, I believe Xamarin Forms' "<strong>VerticalOptions="FillAndExpand"</strong>" uses "<strong>android:layout_alignParentXXX</strong>" instead of "<strong>android:layout_height="match_parent"</strong>".
  Is there any way to make sure to use "<strong>android:layout_height="match_parent"</strong>" by Xamarin.Forms?</p>
  
  <p>Regards,</p>
  
  <p>Kohei</p>