title: C#/AvaloniaUI - Click a button and change Text
body: <p>I am very new to AvaloniaUI.</p>
  
  <p>I am really struggling to change a text when I click a button.
  Here is my code:</p>
  
  <pre><code>  &lt;Window xmlns="https://github.com/avaloniaui"
            xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
            xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
            xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
            mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
            x:Class="ReadyForWar_Launcher.MainWindow"
            Title="ReadyForWar_Launcher"&gt;
      &lt;StackPanel&gt;
        &lt;TextBlock Name="TestBlock"&gt;Show my text here!&lt;/TextBlock&gt;
        &lt;Button Command="{Binding RunTheThing}" CommandParameter="Hello World"&gt;Change the Text!&lt;/Button&gt;
      &lt;/StackPanel&gt;
    &lt;/Window&gt;
  </code></pre>
  
  <p>Here is my MainWindow.xaml.cs:</p>
  
  <pre><code>using Avalonia;
  using Avalonia.Controls;
  using Avalonia.Markup.Xaml;
  
  namespace ReadyForWar_Launcher
  {
      public class MainWindow : Window
      {
          public MainWindow()
          {
              InitializeComponent();
  #if DEBUG
              this.AttachDevTools();
  #endif
          }
  
          private void InitializeComponent()
          {
              AvaloniaXamlLoader.Load(this);
          }
  
          public void RunTheThing()
          {
  
          }
      }
  }
  </code></pre>
  
  <p>Inside <code>RunTheThing</code> I don't know how can I select the TextBlock with Name="TestBlock" and change the text to "Hello World".</p>
  
  <p>Can you please help me out on this ?</p>