title: How to open a child Window like a splash screen before MainWindow in WPF?
body: <p>I have two xaml. One is MainWindow and other is NewWindow.
  I want show NewWindow 5 seconds, when program is run.
  And after 5 seconds, I want show MainWindow.</p>
  
  <p>How to change xaml in WPF?</p>
  
  <p>Here is MainWindow.</p>
  
  <pre><code>&lt;Window x:Class="WpfApplication2.MainWindow"
      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
      Title="MainWindow" Height="350" Width="525"&gt;
  &lt;Grid&gt;
  
  &lt;/Grid&gt;
  </code></pre>
  
  <p></p>
  
  <pre><code>public partial class MainWindow : Window
  {
      public MainWindow()
      {
          InitializeComponent();
      }
  }
  </code></pre>
  
  <p>Here is NewWindow.</p>
  
  <pre><code>&lt;Window x:Class="WpfApplication2.NewWindow"
      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
      Title="NewWindow" Height="300" Width="300"&gt;
  &lt;Grid&gt;
  
  &lt;/Grid&gt;
  </code></pre>
  
  <p></p>
  
  <pre><code>public partial class NewWindow : Window
  {
      public NewWindow()
      {
          InitializeComponent();
      }
  }
  </code></pre>