AutoSuggestTextBoxWithTemplate.xaml

<UserControl x:Class="MaterialDesignThemes.UITests.Samples.AutoSuggestTextBoxes.AutoSuggestTextBoxWithTemplate"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             xmlns:local="clr-namespace:MaterialDesignThemes.UITests.Samples.AutoSuggestTextBoxes"
             xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
             d:DataContext="{d:DesignInstance Type=local:AutoSuggestTextBoxWithTemplateViewModel}"
             mc:Ignorable="d" 
             d:DesignHeight="450" d:DesignWidth="800">
  <materialDesign:AutoSuggestBox
      materialDesign:HintAssist.HelperText="Name"
      materialDesign:TextFieldAssist.HasClearButton="True"
      Text="{Binding AutoSuggestText, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"
      Suggestions="{Binding Suggestions}"
      ValueMember="Name"
      DisplayMember="Name">
  </materialDesign:AutoSuggestBox>
</UserControl>