UI Page inside class library - windows-8

Question

I am developing a class library in Windows 8 (C#), in which i require to show an UI to get user input. How to create UI inside class library and invoking it. Please help.
Now I am invoking the Popup from class library to show the required UI, but I found the popup is opening from library but its hiding below the other UI element (Webview in my case).Please refer the code snippet below.
Class library code
namespace PopUpLibrary
{
public class PopupDialog
{
public void ShowPopup()
{
Popup popup = new Popup();
popup.HorizontalAlignment = HorizontalAlignment.Center;
popup.VerticalAlignment = VerticalAlignment.Center;
popup.Height = 500;
popup.Width = 700;
Button button = new Button();
button.Content = "adfadfad";
button.Width = 200;
button.Height = 100;
popup.Child = button;
popup.IsOpen = true;
}
}
}
Application code:
MainPage.xaml
<Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">
<WebView Name="webview" ></WebView>
</Grid>
MainPage.xaml.cs
public MainPage()
{
this.InitializeComponent();
webview.Navigate(new Uri("http://www.google.com"));
PopupDialog popupdialog = new PopupDialog();
popupdialog.ShowPopup();
}

Answer 1

You cannot show other controls on top of the WebView. However, you can work around this by temporarily hiding the WebView and displaying a WebViewBrush.
From the WebView Documentation:
WebView has the characteristic that other UI regions such as controls cannot be rendered on top of the WebView. This is because of how window regions are handled internally, particularly how input events are processed and how the screen draws. If you want to render HTML content and also place other UI elements on top of that HTML content, you should use WebViewBrush as the render area. The WebView still provides the HTML source information, and you reference that WebView through the SourceName property. WebViewBrush does not have this overlay limitation.
If you want to display an interactive WebView that only occasionally has overlapping content (such as a drop-down list or app bar), you can temporarily hide the WebView control when necessary, replacing it with an element using a WebViewBrush fill. Then, when the overlapping content is no longer present, you can display the original WebView again. For more info, see the WebView control sample.

Answer 2

What kind of input? Yes/No or string input?
For Yes/No you could use the standard MessageDialog. If you need to receive custom input, such as text, you could use the CustomDialog control, available in the Callisto toolkit.