title: Change a TextView's text
body: <p>I am using Xamarin and I have a TextView loaded via an XML layout file with the following code:</p>
  
  <pre><code>SetContentView (Resource.Layout.TextView);
  </code></pre>
  
  <p>Once the TextView is loaded onscreen, how can I change the Text of the TextView? How can I refer to the TextView via code as I have not declared it as a variable?</p>
  
  <p>I have tried this with no result:</p>
  
  <pre><code>TextView PhoneNumber = (TextView)FindViewById(Resource.Layout.TextView);
  PhoneNumber.Text = "This is a phone number: 0800 64 64 64";
  </code></pre>
  
  <p>The TextView is not displayed onscreen at all.</p>
  
  <p>Can I please have some help?</p>
  
  <p>Thanks in advance.</p>