title: How to I handle keyboard appearance/disappearance in xamarin.forms
body: <p>I have a topmost grid</p>
  
  <pre><code>&lt;Grid.RowDefinitions&gt;
  &lt;RowDefinition Height="*"/&gt;
  &lt;RowDefinition Height="120"/&gt;
  &lt;RowDefinition Height="1"/&gt;
  &lt;RowDefinition Height="5"/&gt;
  &lt;RowDefinition Height="35"/&gt;
  &lt;RowDefinition Height="5"/&gt;
  &lt;/Grid.RowDefinitions&gt;
  </code></pre>
  
  <p>in my page.
  How could I have * row to adjust it's height to respect the presence or absence of on screen keyboard?
  So that the content in the row 0 shrinks as the keyboard appears.
  Or, at the very least how could I detect keyboard shows up
  on an Editor?
  I have a custom renderer for that Editor already
  so stuffing extra platform specific code can be done swiftly.</p>