Getting Started with .NET MAUI Expander (SfExpander)

7 Feb 202524 minutes to read

This section guides you through setting up and configuring a Expander in your .NET MAUI application. Follow the steps below to add a basic Expander to your project.

• Visual Studio
• Visual Studio Code
• JetBrains Rider

Prerequisites

Before proceeding, ensure the following are in place:

1. Install .NET 8 SDK or later.
2. Set up a .NET MAUI environment with Visual Studio 2022 (v17.12 or later) or VS Code.

Step 1: Create a .NET MAUI project

1. Go to File > New > Project and choose the .NET MAUI App template.
2. Name the project and choose a location. Then, click Next.
3. Select the .NET framework version and click Create.

Step 2: Install the Syncfusion MAUI ToolKit NuGet Package

1. In Solution Explorer, right-click the project and choose Manage NuGet Packages.
2. Search for Syncfusion.Maui.ToolKit and install the latest version.
3. Ensure the necessary dependencies are installed correctly, and the project is restored.

Step 3: Register the handler

In the MauiProgram.cs file, register the handler for Syncfusion^® Toolkit.

MauiProgram.cs

using Syncfusion.Maui.Toolkit.Hosting;

public class MauiProgram 
{
    public static MauiApp CreateMauiApp()
    {
        var builder = MauiApp.CreateBuilder();
        builder
        .UseMauiApp<App>()
        .ConfigureFonts(fonts =>
        {
            fonts.AddFont("OpenSans-Regular.ttf", "OpenSansRegular");
        });

        builder.ConfigureSyncfusionToolkit();
        return builder.Build();
    }
}

Step 4: Add a Basic Expander control

1. To initialize the control, import the Syncfusion.Maui.Toolkit.Expander namespace into your code.

2. Initialize SfExpander class.

XAML

<ContentPage   
    xmlns:syncfusion=xmlns:syncfusion="clr-namespace:Syncfusion.Maui.Toolkit.Expander;assembly=Syncfusion.Maui.Toolkit">
    <syncfusion:SfExpander />
</ContentPage>

C#

using Syncfusion.Maui.Toolkit.Expander;
. . .
public partial class MainPage : ContentPage
{
    public MainPage()
    {
        InitializeComponent();
        SfExpander expander = new SfExpander();
    }
}

Prerequisites

Before proceeding, ensure the following are set up:

1. Install .NET 8 SDK or later is installed.
2. Set up a .NET MAUI environment with Visual Studio Code.
3. Ensure that the .NET MAUI extension is installed and configured as described here.

Step 1: Create a new .NET MAUI Project

1. Open the command palette by pressing Ctrl+Shift+P and type .NET:New Project and enter.
2. Choose the .NET MAUI App template.
3. Select the project location, type the project name and press Enter.
4. Then choose Create project.

Step 2: Install the Syncfusion^® MAUI Core NuGet Package

1. Press Ctrl + ` (backtick) to open the integrated terminal in Visual Studio Code.
2. Ensure you’re in the project root directory where your .csproj file is located.
3. Run the command dotnet add package Syncfusion.Maui.Toolkit to install the Syncfusion^® .NET MAUI Toolkit NuGet package.
4. To ensure all dependencies are installed, run dotnet restore.

Step 3: Register the handler

In the MauiProgram.cs file, register the handler for Syncfusion^® Toolkit.

MauiProgram.cs

using Syncfusion.Maui.Toolkit.Hosting;

public class MauiProgram 
{
    public static MauiApp CreateMauiApp()
    {
        var builder = MauiApp.CreateBuilder();
        builder
        .UseMauiApp<App>()
        .ConfigureFonts(fonts =>
        {
            fonts.AddFont("OpenSans-Regular.ttf", "OpenSansRegular");
        });

        builder.ConfigureSyncfusionToolkit();
        return builder.Build();
    }
}

Step 4: Add a Basic Expander control

1. To initialize the control, import the Syncfusion.Maui.Toolkit.Expander namespace into your code.

2. Initialize SfExpander class.

XAML

<ContentPage   
    xmlns:syncfusion=xmlns:syncfusion="clr-namespace:Syncfusion.Maui.Toolkit.Expander;assembly=Syncfusion.Maui.Toolkit">
    <syncfusion:SfExpander />
</ContentPage>

C#

using Syncfusion.Maui.Toolkit.Expander;
. . .
public partial class MainPage : ContentPage
{
    public MainPage()
    {
        InitializeComponent();
        SfExpander expander = new SfExpander();
    }
}

Prerequisites

Before proceeding, ensure the following are set up:

1. Ensure you have the latest version of JetBrains Rider.
2. Install .NET 8 SDK or later is installed.
3. Make sure the MAUI workloads are installed and configured as described here.

Step 1: Create a new .NET MAUI Project

1. Go to File > New Solution, Select .NET (C#) and choose the .NET MAUI App template.
2. Enter the Project Name, Solution Name, and Location.
3. Select the .NET framework version and click Create.

Step 2: Install the Syncfusion^® MAUI Toolkit NuGet Package

1. In Solution Explorer, right-click the project and choose Manage NuGet Packages.
2. Search for Syncfusion.Maui.Toolkit and install the latest version.
3. Ensure the necessary dependencies are installed correctly, and the project is restored. If not, Open the Terminal in Rider and manually run: dotnet restore

Step 3: Register the handler

In the MauiProgram.cs file, register the handler for Syncfusion^® Toolkit.

MauiProgram.cs

using Syncfusion.Maui.Toolkit.Hosting;

public class MauiProgram 
{
    public static MauiApp CreateMauiApp()
    {
        var builder = MauiApp.CreateBuilder();
        builder
        .UseMauiApp<App>()
        .ConfigureFonts(fonts =>
        {
            fonts.AddFont("OpenSans-Regular.ttf", "OpenSansRegular");
        });

        builder.ConfigureSyncfusionToolkit();
        return builder.Build();
    }
}

Step 4: Add a Basic Expander control

1. To initialize the control, import the Syncfusion.Maui.Toolkit.Expander namespace into your code.

2. Initialize SfExpander class.

XAML

<ContentPage   
    xmlns:syncfusion=xmlns:syncfusion="clr-namespace:Syncfusion.Maui.Toolkit.Expander;assembly=Syncfusion.Maui.Toolkit">
    <syncfusion:SfExpander />
</ContentPage>

C#

using Syncfusion.Maui.Toolkit.Expander;
. . .
public partial class MainPage : ContentPage
{
    public MainPage()
    {
        InitializeComponent();
        SfExpander expander = new SfExpander();
    }
}

Step 5: Define the Header and Content

The SfExpander is a layout control that includes a Header and a Content section, where any view can be loaded. The visibility of the content can be controlled using the IsExpanded property. Users can expand or collapse the content view by tapping the header.

Here, the grid with label is loaded in the header and content of the expander.

NOTE

Loading the Label as direct children of the Header or Content of the Expander will lead to an exception. So, load the Label inside the Grid to overcome the crash.

XAML

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:syncfusion="clr-namespace:Syncfusion.Maui.Toolkit.Expander;assembly=Syncfusion.Maui.Toolkit"
             x:Class="GettingStarted.MainPage">
    <ContentPage.Content>
        <ScrollView >
            <StackLayout  HorizontalOptions="{OnPlatform MacCatalyst=Center,WinUI=Center}"  >
                <Label Text="Invoice: #FRU037020142097"  Opacity="1.0" VerticalTextAlignment="Center" Margin="0,0,0,5" FontAttributes="Bold" VerticalOptions="Center" HorizontalOptions="CenterAndExpand"/>
                <Border StrokeShape="RoundRectangle 8,8,8,8" Margin="{OnPlatform Default='8,0,8,8',WinUI='8,0,6,8',MacCatalyst='8,0,6,8'}" Stroke="#CAC4D0"  StrokeThickness="{OnPlatform MacCatalyst=2,Default=1}" WidthRequest="{OnPlatform MacCatalyst=460,WinUI=340}">
                    <syncfusion:SfExpander AnimationDuration="200" IsExpanded="True" >
                        <syncfusion:SfExpander.Header>
                            <Grid >
                                <Grid.RowDefinitions>
                                    <RowDefinition Height="48"/>
                                </Grid.RowDefinitions>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="35"/>
                                    <ColumnDefinition Width="*"/>
                                </Grid.ColumnDefinitions>
                                <Label Text="&#xe703;" FontSize="16" Margin="14,2,2,2"
                                                   FontFamily='{OnPlatform Android=AccordionFontIcons.ttf#,WinUI=AccordionFontIcons.ttf#AccordionFontIcons,MacCatalyst=AccordionFontIcons,iOS=AccordionFontIcons}'
                                                   VerticalOptions="Center" VerticalTextAlignment="Center"/>
                                <Label CharacterSpacing="0.25" FontFamily="Roboto-Regular"  Text="Invoice Date" FontSize="14" Grid.Column="1" VerticalOptions="CenterAndExpand"/>
                            </Grid>
                        </syncfusion:SfExpander.Header>
                        <syncfusion:SfExpander.Content>
                            <Grid Padding="18,8,0,18" >
                                <Label CharacterSpacing="0.25" FontFamily="Roboto-Regular"  Text="11:03 AM, 15 January 2019" FontSize="14" VerticalOptions="CenterAndExpand"/>
                            </Grid>
                        </syncfusion:SfExpander.Content>
                    </syncfusion:SfExpander>
                </Border>
                <Border StrokeShape="RoundRectangle 8,8,8,8" Margin="{OnPlatform Default='8,0,8,8',WinUI='8,0,6,8',MacCatalyst='8,0,6,8'}" Stroke="#CAC4D0"  StrokeThickness="{OnPlatform MacCatalyst=2,Default=1}" WidthRequest="{OnPlatform MacCatalyst=460,WinUI=340}">
                    <syncfusion:SfExpander  AnimationDuration="200" IsExpanded="False">
                        <syncfusion:SfExpander.Header>
                            <Grid>
                                <Grid.RowDefinitions>
                                    <RowDefinition Height="48"/>
                                </Grid.RowDefinitions>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="35"/>
                                    <ColumnDefinition Width="*"/>
                                </Grid.ColumnDefinitions>
                                <Label Text="&#xe701;" FontSize="16" Margin="14,2,2,2"
                                                   FontFamily='{OnPlatform Android=AccordionFontIcons.ttf#,WinUI=AccordionFontIcons.ttf#AccordionFontIcons,MacCatalyst=AccordionFontIcons,iOS=AccordionFontIcons}'
                                                   VerticalOptions="Center" VerticalTextAlignment="Center"/>
                                <Label CharacterSpacing="0.25" FontFamily="Roboto-Regular"  Text="Item(s)" FontSize="14" Grid.Column="1" VerticalOptions="CenterAndExpand"/>
                            </Grid>
                        </syncfusion:SfExpander.Header>
                        <syncfusion:SfExpander.Content>
                            <Grid Padding="18,8,18,18">
                                <Grid.RowDefinitions>
                                    <RowDefinition Height="20"/>
                                    <RowDefinition Height="20"/>
                                    <RowDefinition Height="20"/>
                                    <RowDefinition Height="20"/>
                                    <RowDefinition Height="20"/>
                                    <RowDefinition Height="20"/>
                                    <RowDefinition Height="20"/>
                                </Grid.RowDefinitions>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="*"/>
                                    <ColumnDefinition Width="*"/>
                                </Grid.ColumnDefinitions>
                                <Label FontSize="14" CharacterSpacing="0.25"  Text="2018 Subaru Outback"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  Text="All-Weather Mats" Grid.Row="1"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  Text="Door Edge Guard Kit" Grid.Row="2"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  Text="Rear Bumper Cover" Grid.Row="3"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  Text="Wheel Locks" Grid.Row="4"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  Text="Gas Full Tank" Grid.Row="5"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  Text="Total Amount" TextColor="{StaticResource Primary}" Grid.Row="6"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  HorizontalOptions="End" Text="$35,705.00" Grid.Row="0" Grid.Column="1"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  HorizontalOptions="End" Text="$101.00" Grid.Row="1" Grid.Column="1"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  HorizontalOptions="End" Text="$162.00" Grid.Row="2" Grid.Column="1"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  HorizontalOptions="End" Text="$107.00" Grid.Row="3" Grid.Column="1"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  HorizontalOptions="End" Text="$81.00" Grid.Row="4" Grid.Column="1"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  HorizontalOptions="End" Text="$64.00" Grid.Row="5" Grid.Column="1"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  HorizontalOptions="End" Text="$36,220.00" TextColor="{StaticResource Primary}" Grid.Row="6" Grid.Column="1"/>
                            </Grid>
                        </syncfusion:SfExpander.Content>
                    </syncfusion:SfExpander>
                </Border>
                <Border StrokeShape="RoundRectangle 8,8,8,8" Margin="{OnPlatform Default='8,0,8,8',WinUI='8,0,6,8',MacCatalyst='8,0,6,8'}" Stroke="#CAC4D0" StrokeThickness="{OnPlatform MacCatalyst=2,Default=1}" WidthRequest="{OnPlatform MacCatalyst=460,WinUI=340}">
                    <syncfusion:SfExpander AnimationDuration="200"  IsExpanded="False">
                        <syncfusion:SfExpander.Header>
                            <Grid>
                                <Grid.RowDefinitions>
                                    <RowDefinition Height="48"/>
                                </Grid.RowDefinitions>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="35"/>
                                    <ColumnDefinition Width="*"/>
                                </Grid.ColumnDefinitions>
                                <Label Text="&#xe702;" FontSize="16" Margin="14,2,2,2"
                                                   FontFamily='{OnPlatform Android=AccordionFontIcons.ttf#,WinUI=AccordionFontIcons.ttf#AccordionFontIcons,MacCatalyst=AccordionFontIcons,iOS=AccordionFontIcons}'
                                                   VerticalOptions="Center" VerticalTextAlignment="Center"/>
                                <Label CharacterSpacing="0.25" FontFamily="Roboto-Regular"  Text="Payment Details" FontSize="14" Grid.Column="1" VerticalOptions="CenterAndExpand"/>
                            </Grid>
                        </syncfusion:SfExpander.Header>
                        <syncfusion:SfExpander.Content>
                            <Grid Padding="18,8,18,18"  RowSpacing="6" >
                                <Grid.RowDefinitions>
                                    <RowDefinition Height="20"/>
                                    <RowDefinition Height="20"/>
                                    <RowDefinition Height="20"/>
                                </Grid.RowDefinitions>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="*"/>
                                    <ColumnDefinition Width="*"/>
                                </Grid.ColumnDefinitions>
                                <Label FontSize="14" CharacterSpacing="0.25"  Text="Card Payment"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  Text="Third-Party coupons" Grid.Row="1"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  Text="Total Amount Paid" TextColor="{StaticResource Primary}" Grid.Row="2"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  HorizontalOptions="End" Text="$31,200.00" Grid.Column="1"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  HorizontalOptions="End" Text="$5,000.00" Grid.Row="1" Grid.Column="1"/>
                                <Label FontSize="14" CharacterSpacing="0.25"  HorizontalOptions="End" Text="$36,200.00" TextColor="{StaticResource Primary}" Grid.Row="2" Grid.Column="1"/>
                            </Grid>
                        </syncfusion:SfExpander.Content>
                    </syncfusion:SfExpander>
                </Border>
                <Border StrokeShape="RoundRectangle 8,8,8,8" Margin="{OnPlatform Default='8,0,8,8',WinUI='8,0,6,8',MacCatalyst='8,0,6,8'}" Stroke="#CAC4D0" StrokeThickness="{OnPlatform MacCatalyst=2,Default=1}" WidthRequest="{OnPlatform MacCatalyst=460,WinUI=340}">
                    <syncfusion:SfExpander AnimationDuration="200" IsExpanded="True">
                        <syncfusion:SfExpander.Header>
                            <Grid>
                                <Grid.RowDefinitions>
                                    <RowDefinition Height="48"/>
                                </Grid.RowDefinitions>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="35"/>
                                    <ColumnDefinition Width="*"/>
                                </Grid.ColumnDefinitions>
                                <Label Text="&#xe704;" FontSize="16" Margin="14,2,2,2"
                                                   FontFamily='{OnPlatform Android=AccordionFontIcons.ttf#,WinUI=AccordionFontIcons.ttf#AccordionFontIcons,MacCatalyst=AccordionFontIcons,iOS=AccordionFontIcons}'
                                                   VerticalOptions="Center" VerticalTextAlignment="Center"/>
                                <Label CharacterSpacing="0.25" FontFamily="Roboto-Regular" FontSize="14" Text="Address" Grid.Column="1" VerticalOptions="CenterAndExpand"/>
                            </Grid>
                        </syncfusion:SfExpander.Header>
                        <syncfusion:SfExpander.Content>
                            <Grid Padding="18,8,18,18" Grid.Row="1" RowSpacing="1">
                                <Grid.RowDefinitions >
                                    <RowDefinition Height="Auto"/>
                                    <RowDefinition Height="Auto"/>
                                    <RowDefinition Height="Auto"/>
                                </Grid.RowDefinitions>
                                <Label CharacterSpacing="0.25"  FontSize="14" Text="Alex" FontAttributes="Bold"/>
                                <Label CharacterSpacing="0.25"  FontSize="14" Text="No.8 Blossom St, Washington, DC 20019" Grid.Row="1"/>
                                <Label CharacterSpacing="0.25"  FontSize="14" Text="[phone]" Grid.Row="2"/>
                            </Grid>
                        </syncfusion:SfExpander.Content>
                    </syncfusion:SfExpander>
                </Border>
            </StackLayout>
        </ScrollView>
    </ContentPage.Content>
</ContentPage>

Step 6: Running the Application

Press F5 to build and run the application. Once compiled, the Expander will be displayed with the data provided.

Here is the result of the previous codes,

Animation duration

The SfExpander allows you to customize the duration of the expanding and collapsing animations by using the AnimationDuration property. By default, the animation duration is set to 300 milliseconds.

XAML

<syncfusion:SfExpander x:Name="expander" 
                           AnimationDuration="250"/>

C#

expander.AnimationDuration = 250;

Animation easing

The SfExpander allows you to customize the rate of change of parameters over time or the animation style by using the AnimationEasing property. By default, the animation easing is set to Linear.

XAML

<syncfusion:SfExpander x:Name="expander"
                           AnimationEasing="SinOut"/>

C#

expander.AnimationEasing = ExpanderAnimationEasing.SinOut;

Expand and collapse

The SfExpander allows users to programmatically expand or collapse its content using the IsExpanded property. Users can manage the expand and collapse actions by handling the Expanding and Collapsing events.

XAML

<syncfusion:SfExpander x:Name="expander" 
                           IsExpanded="True"/>

C#

expander.IsExpanded = true;

Events

There are four built-in events in the SfExpander control namely:

• Expanding
• Expanded
• Collapsing
• Collapsed

Expanding Event

The Expanding event will be triggered when the expander control is being expanded.Expansion can be canceled using the ExpandingAndCollapsingEventArgs, which includes the following property:

• Cancel: Indicates that the expansion or collapse action should be canceled.

MainPage.xaml

<syncfusion:SfExpander Expanding="SfExpander_Expanding"/>

MainPage.xaml.cs

private void SfExpander_Expanding(object sender, ExpandingAndCollapsingEventArgs e)
{
    e.Cancel = true;
}

Expanded Event

The Expanded event is triggered when the expander is fully expanded. You can execute your own code when this event occurs.

MainPage.xaml

<syncfusion:SfExpander Expanded="SfExpander_Expanded"/>

MainPage.xaml.cs

private void SfExpander_Expanded(object sender, ExpandedAndCollapsedEventArgs e)
{
    // Codes that need to be executed once the expander is expanded.
}

Collapsing Event

The Collapsing event will be triggered when the expander control is being collapsed.Collapsing can be canceled using the ExpandingAndCollapsingEventArgs, which includes the following property:

• Cancel: Indicates that the expansion or collapse action should be canceled.

MainPage.xaml

<syncfusion:SfExpander Collapsing="SfExpander_Collapsing"/>

MainPage.xaml.cs

private void SfExpander_Collapsing(object sender, ExpandingAndCollapsingEventArgs e)
{
    e.Cancel = true;
}

Collapsed Event

The Collapsed event is triggered when the expander is collapsed. You can execute your own code when this event occurs.

MainPage.xaml

<syncfusion:SfExpander Collapsed="SfExpander_Collapsed"/>

MainPage.xaml.cs

private void SfExpander_Collapsed(object sender, ExpandedAndCollapsedEventArgs e)
{
    // Codes that need to be executed once the expander is collapsed.
}