title: MahApps Metro DialogBox not showing text and background
body: <p>I have this <code>WPF</code> (<code>MVVM</code>) application where I'm using <code>MahApps</code>, where I have :</p>
  
  <ul>
  <li>The <code>Client</code> Project (basically the main WPF project)</li>
  <li><code>Helpers</code> Project</li>
  <li><code>Styling</code> Project</li>
  </ul>
  
  <p>In the Helpers project I have <code>Helper</code> class that fires the <code>ShowMessageAsync</code> methods for me :</p>
  
  <pre><code>public static class ShowMessageBox
  {
      public static async Task Show(MetroWindow metroWindow, string titre, string errorMessage, string errorDetails, string errorHelpLink)
      {
  
          var mySettings = new MetroDialogSettings()
          {
              AffirmativeButtonText = "Ok",
              NegativeButtonText = "Annuler",
              ColorScheme = MetroDialogColorScheme.Accented,
              AnimateShow = true,
              AnimateHide = true
          };
          await metroWindow.ShowMessageAsync(titre, string.Format(errorMessage + " ! \n {0} ... \n {1}",
                                             errorDetails, errorHelpLink), MessageDialogStyle.Affirmative, mySettings);
      }
   //...
  </code></pre>
  
  <p>In the Styling Project I call the MahApps resources in a <code>MahApps.xaml</code> file  : </p>
  
  <pre><code>&lt;ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"&gt;
      &lt;ResourceDictionary.MergedDictionaries&gt;
          &lt;ResourceDictionary Source="pack://application:,,,/MahApps.Metro;component/Styles/Fonts.xaml" /&gt;
          &lt;ResourceDictionary Source="pack://application:,,,/MahApps.Metro;component/Styles/Colors.xaml" /&gt;
          &lt;ResourceDictionary Source="pack://application:,,,/MahApps.Metro;component/Styles/Accents/orange.xaml" /&gt;
          &lt;ResourceDictionary Source="pack://application:,,,/MahApps.Metro;component/Styles/Accents/baselight.xaml" /&gt;
          &lt;ResourceDictionary Source="pack://application:,,,/MahApps.Metro;component/Styles/Controls.xaml" /&gt;
      &lt;/ResourceDictionary.MergedDictionaries&gt;
  
  &lt;/ResourceDictionary&gt;
  </code></pre>
  
  <p>And I reference that from my <code>App.Xaml</code> hence :</p>
  
  <pre><code>&lt;Application.Resources&gt;
  
      &lt;ResourceDictionary&gt;
          &lt;valueConverters:ContentLengthToInvertedBooleanConverter x:Key="ContentLengthToInvertedBooleanConverter" /&gt;
          &lt;valueConverters:ContentLengthToBooleanConverter x:Key="ContentLengthToBooleanConverter" /&gt;
          &lt;viewModels:ViewModelLocator x:Key="Locator" d:IsDataSource="True" /&gt;
          &lt;valueConverters:ListToIsEnabledConverter x:Key="ListToIsEnabledConverter" /&gt;
          &lt;ResourceDictionary.MergedDictionaries&gt;
  
              &lt;ResourceDictionary Source="pack://application:,,,/Styling;component/MahApps.xaml" /&gt;
              &lt;ResourceDictionary Source="pack://application:,,,/Styling;component/Styles.xaml" /&gt;
              &lt;ResourceDictionary Source="pack://application:,,,/Styling;component/Brushes.xaml" /&gt;
              &lt;ResourceDictionary Source="pack://application:,,,/Styling;component/Assets/Assets.xaml" /&gt;
          &lt;/ResourceDictionary.MergedDictionaries&gt;
      &lt;/ResourceDictionary&gt;
  
  &lt;/Application.Resources&gt;
  </code></pre>
  
  <p>When I fire a the <code>MessageDialog</code> (in a certain ViewModel) :</p>
  
  <pre><code>var mainWindow = (MetroWindow)Application.Current.MainWindow;
  await ShowMessageBox.Show(mainWindow, "Ajout !",
                      "Marque Ajoutée avec succés !", String.Empty, String.Empty,
                      0);
  </code></pre>
  
  <p>Here's what I get :</p>
  
  <p><a href="https://i.stack.imgur.com/EfXLf.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/EfXLf.png" alt="enter image description here"></a></p>
  
  <p>All what I get is that little <code>Ok</code> button that follows the accent correctly, but no White background, no text, no anything else. Note that I'm referencing MahApps.Metro in each project, What's wrong ? How can I correct this ?? </p>