title: Send data from a UserControl in a Popup to the parent Page
body: <p>I have a Popup that's just a UserControl which is basically just a form to fill out with a 'Done' button on it.  I can't find a way to send the data from the form to the Page so that I can parse and use the data to create a specific element.  Basically when the 'Done' button is clicked I can't find a way to send or even access the Page to store the data.</p>
  
  <p>Binding doesn't seem to be the way to go either as when the 'Done' button is clicked what happens is the Page creates another UserControl populated with the data that was received from the form in the popup.  Since binding doesn't seem to fit my problem, passing data would be next but since I can't find a way to reference the Page I can't get this solution to work either.</p>
  
  <p>the Page is just this:</p>
  
  <pre><code>&lt;Button HorizontalAlignment="Left" Margin="227,115,0,0" VerticalAlignment="Top"&gt;
      &lt;Popup IsLightDismissEnabled="True"&gt;
          &lt;local:PopupMenu/&gt;
      &lt;/Popup&gt;
  &lt;/Button&gt;
  &lt;TextBox HorizontalAlignment="Left" Margin="230,340,0,0" TextWrapping="Wrap" Text="0" VerticalAlignment="Top" Height="55" Width="455"/&gt;
  </code></pre>
  
  <p>The UserControl is basically:</p>
  
  <pre><code>&lt;UserControl
  x:Class="SimpleShop.PopupMenu"
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:local="using:SimpleShop"
  xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
  xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
  mc:Ignorable="d" Height="800" Width="1295"&gt;
  &lt;TextBlock text="Enter A Number" Fontsize="24" TextWrapping="Wrap" Height="40" Width="200"  /&gt;
  &lt;TextBox x:Name="Number1" Text="0" TextWrapping="Wrap" Height="40" Width="200"  /&gt;
  &lt;TextBlock text="Enter A Number" Fontsize="24" TextWrapping="Wrap" Height="40" Width="200"  /&gt;
  &lt;TextBox x:Name="Number2" Text="0" TextWrapping="Wrap" Height="40" Width="200" /&gt;
  &lt;Button x:Name="AddItemButton" Content="Button" FontSize="24"  Height="40" Width="110" Click="AddItemButton_Click" /&gt;
  &lt;/UserControl&gt;
  </code></pre>
  
  <p>So what happens is when the button on the page is pressed the popup appears, after 2 numbers are entered and the button on the popup is pressed the textbox on the page is updated with the result of the 2 entered numbers being multiplied and the popup is closed.  The problem i'm having is updating the textbox on the page after the button on the popup is pressed.  I can't find a way to point to or reference the textbox.</p>