In the MahApps Metro UI, specifically the MetroWindow we can turn the drop shadow on using the following. In code…
BorderlessWindowBehavior b = new BorderlessWindowBehavior
{
EnableDWMDropShadow = true,
AllowsTransparency = false
};
BehaviorCollection bc = Interaction.GetBehaviors(window);
bc.Add(b);
Note: We must set the Allow Transparency to false to use the EnableDWMDropShadow.
In XAML, we can use the following
<i:Interaction.Behaviors>
<behaviours:BorderlessWindowBehavior
AllowsTransparency="False"
EnableDWMDropShadow="True" />
</i:Interaction.Behaviors>