The colors of the buttons should be swapped.
When calling the follwing code:
MetroDialogSettings dialogSettings = new MetroDialogSettings();
dialogSettings.CustomResourceDictionary = new ResourceDictionary
{
Source = new Uri("NETworkManager;component/Resources/Styles/MetroDialogStyles.xaml", UriKind.RelativeOrAbsolute)
};
await dialogCoordinator.ShowMessageAsync(this, "Error", "Could not resolve host name", MessageDialogStyle.AffirmativeAndNegative,dialogSettings)
MetroDialogStyles.xaml
<Style BasedOn="{StaticResource MetroFlatButton}" TargetType="{x:Type Button}" />
<Style x:Key="AccentedDialogSquareButton"
BasedOn="{StaticResource MetroFlatButton}"
TargetType="{x:Type Button}">
<Setter Property="Foreground" Value="{DynamicResource WhiteColorBrush}" />
<Setter Property="Background" Value="{DynamicResource AccentColorBrush}" />
</Style>
<Style x:Key="AccentedDialogHighlightedSquareButton"
BasedOn="{StaticResource MetroFlatButton}"
TargetType="{x:Type Button}">
<Setter Property="Foreground" Value="{DynamicResource WhiteColorBrush}" />
<Setter Property="Background" Value="{DynamicResource HighlightBrush}" />
</Style>
It looks like this:

Shouldn't be the OK-Button highlighted?
The "OK" Button should be highlighted...
https://github.com/BornToBeRoot/NETworkManager
Try setting the DefaultButtonFocus to MessageDialogResult.Affirmative in the MetroDialogSettings.
Like @Deadpikle said. The default value for MetroDialogSettings.DefaultButtonFocus is MessageDialogResult.Negative, see
https://github.com/MahApps/MahApps.Metro/blob/develop/src/MahApps.Metro/MahApps.Metro.Shared/Controls/Dialogs/BaseMetroDialog.cs#L394
@Deadpikle @thoemmi Thanks!
This would be great in the documentation馃槂
Edit: It was a bit confusing, because when i use ShowInputAsync the default/highlighted button is set to Affirmative...
Most helpful comment
Try setting the
DefaultButtonFocustoMessageDialogResult.Affirmativein theMetroDialogSettings.