Dealing with SuggestionBox in UWP AutoComplete (SfTextBoxExt)

The suggestion box is a drop-down list box that displays the filtered suggestions inside a popup. This section explains the properties that deal with drop-down list in the AutoComplete control.

SuggestionBox placement mode

The suggestion box can be placed either at the top or bottom using the SuggestionBoxPlacement property. By default, it is placed at the bottom.

<Page
    x:Class="TextBoxExtSample.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:TextBoxExtSample"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    xmlns:editors="using:Syncfusion.UI.Xaml.Controls.Input"
    Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">

    <Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">

        <editors:SfTextBoxExt x:Name="textBoxExt" 
                              HorizontalAlignment="Center" 
                              VerticalAlignment="Center" 
                              AutoCompleteMode="Suggest"
                              SuggestionBoxPlacement="Top"
                              Width="200">
        </editors:SfTextBoxExt>
    </Grid>
</Page>
using Syncfusion.UI.Xaml.Controls.Input;
using System.Collections.Generic;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;

// The BlankPage item template is documented at https://go.microsoft.com/fwlink/?LinkId=402352&clcid=0x409.

namespace TextBoxExtSample
{
    /// <summary>
    /// An empty page that can be used on its own or navigated within a frame.
    /// </summary>
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();
            SfTextBoxExt textBoxExt = new SfTextBoxExt()
            {
                HorizontalAlignment = HorizontalAlignment.Center,
                VerticalAlignment = VerticalAlignment.Center,
                Width = 200,
                AutoCompleteMode = AutoCompleteMode.Suggest,
                SuggestionBoxPlacement = SuggestionBoxPlacement.Top
            };

            List<string> list = new List<string>()
            {
                 "India",
                 "Uganda",
                 "Ukraine",
                 "Canada",
                 "United Arab Emirates"
            };

            textBoxExt.AutoCompleteSource = list;
            this.Content = textBoxExt;
        }
    }
}

SuggestionBoxPlacement

Maximum suggestion box height

The maximum height of the suggestion box in the Autocomplete control can be changed using the MaximumDropDownHeight property.

<Page
    x:Class="TextBoxExtSample.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:TextBoxExtSample"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    xmlns:editors="using:Syncfusion.UI.Xaml.Controls.Input"
    Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">

    <Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">

        <editors:SfTextBoxExt x:Name="textBoxExt" 
                              HorizontalAlignment="Center" 
                              VerticalAlignment="Center" 
                              AutoCompleteMode="Suggest"
                              MaxDropDownHeight="500"
                              Width="200">
        </editors:SfTextBoxExt>
    </Grid>
</Page>
using Syncfusion.UI.Xaml.Controls.Input;
using System.Collections.Generic;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;

// The BlankPage item template is documented at https://go.microsoft.com/fwlink/?LinkId=402352&clcid=0x409.

namespace TextBoxExtSample
{
    /// <summary>
    /// An empty page that can be used on its own or navigated within a frame.
    /// </summary>
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();
            SfTextBoxExt textBoxExt = new SfTextBoxExt()
            {
                HorizontalAlignment = HorizontalAlignment.Center,
                VerticalAlignment = VerticalAlignment.Center,
                Width = 200,
                AutoCompleteMode = AutoCompleteMode.Suggest,
                MaxDropDownHeight = 500
            };

            List<string> list = new List<string>()
            {
                 "India",
                 "Uganda",
                 "Ukraine",
                 "Canada",
                 "United Arab Emirates"
            };

            textBoxExt.AutoCompleteSource = list;
            this.Content = textBoxExt;
        }
    }
}

MaximumDropDownHeight

Opening suggestion box on focus

The suggestion box can be shown whenever the control receives focus using the ShowSuggestionsOnFocus property. At this time, suggestion list is the complete list of data source.

<Page
    x:Class="TextBoxExtSample.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:TextBoxExtSample"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    xmlns:editors="using:Syncfusion.UI.Xaml.Controls.Input"
    Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">

    <Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">

        <editors:SfTextBoxExt x:Name="textBoxExt" 
                              HorizontalAlignment="Center" 
                              VerticalAlignment="Center" 
                              AutoCompleteMode="Suggest"
                              ShowSuggestionsOnFocus="True"
                              Width="200">
        </editors:SfTextBoxExt>
    </Grid>
</Page>
using Syncfusion.UI.Xaml.Controls.Input;
using System.Collections.Generic;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;

// The BlankPage item template is documented at https://go.microsoft.com/fwlink/?LinkId=402352&clcid=0x409.

namespace TextBoxExtSample
{
    /// <summary>
    /// An empty page that can be used on its own or navigated within a frame.
    /// </summary>
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();
            SfTextBoxExt textBoxExt = new SfTextBoxExt()
            {
                HorizontalAlignment = HorizontalAlignment.Center,
                VerticalAlignment = VerticalAlignment.Center,
                Width = 200,
                AutoCompleteMode = AutoCompleteMode.Suggest,
                ShowSuggestionsOnFocus = true
            };

            List<string> list = new List<string>()
            {
                 "India",
                 "Uganda",
                 "Ukraine",
                 "Canada",
                 "United Arab Emirates"
            };

            textBoxExt.AutoCompleteSource = list;
            this.Content = textBoxExt;
        }
    }
}

SuggestionsOnFocus

Avoid opening suggestion box

The APIs are available to avoid opening the popups. By setting the SuggestionBoxPlacement API to None, you can avoid opening suggestion box.

<Page
    x:Class="TextBoxExtSample.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:TextBoxExtSample"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    xmlns:editors="using:Syncfusion.UI.Xaml.Controls.Input"
    Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">

    <Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">

        <editors:SfTextBoxExt x:Name="textBoxExt" 
                              HorizontalAlignment="Center" 
                              VerticalAlignment="Center" 
                              AutoCompleteMode="Suggest"
                              Width="200"
                              SuggestionBoxPlacement="None">
        </editors:SfTextBoxExt>
    </Grid>
</Page>
using Syncfusion.UI.Xaml.Controls.Input;
using System.Collections.Generic;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;

// The BlankPage item template is documented at https://go.microsoft.com/fwlink/?LinkId=402352&clcid=0x409.

namespace TextBoxExtSample
{
    /// <summary>
    /// An empty page that can be used on its own or navigated within a frame.
    /// </summary>
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();
            SfTextBoxExt textBoxExt = new SfTextBoxExt()
            {
                HorizontalAlignment = HorizontalAlignment.Center,
                VerticalAlignment = VerticalAlignment.Center,
                Width = 200,
                AutoCompleteMode = AutoCompleteMode.Suggest,
                SuggestionBoxPlacement = SuggestionBoxPlacement.None
            };

            List<string> list = new List<string>()
            {
                 "James",
                 "Jacob",
                 "Lucas"
            };

            textBoxExt.AutoCompleteSource = list;
            this.Content = textBoxExt;
        }
    }
}

SuggestionBoxPlacement_None

NOTE

In None mode, the drop-down list will not open but the Suggestions property of SfTextBoxExt gets filled with filtered suggestions so users who want to display the suggestions in a separate list box can use this option.