Coding4Fun

Setting Up the InnerTube WPF Application

Now that you've seen the core libraries, let's show how you can build a WPF application that can display our list of videos. The first thing we need to do is set up a couple of conventions for our application, namely where we will store global variables, such as the list of feeds and our application setting variables, whether iTunes or Zune is installed, and what location we will save downloaded videos to.

Global Variables

When you create a WPF project, it includes an Application class named App.xaml, which includes a code-behind file that, since it's an application-level scope class, would be a perfect place for us to store our global variables. To do that, we declare our list of feeds and our application settings as static properties, as shown in Example 4-53 and Example 4-54.

Example 4-53.  C# code for InnerTube's global variables

public partial class App : Application
{
  public static ObservableCollection<InnerTubeFeed> InnerTubeFeeds { get; set; }
  public static Setting Settings { get; set; }
...

Example 4-54.  Visual Basic code for InnerTube's global variables

Partial Public Class App Inherits Application Private Shared privateInnerTubeFeeds As ObservableCollection(Of InnerTubeFeed) Public Shared Property InnerTubeFeeds() As ObservableCollection(Of ...