.NET MAUI DataGrid Aggregates Styling

The .NET MAUI DataGrid provides a styling functionality for its group footer, header, and column footer aggregates.

Styling the Group Header

The Telerik UI for .NET MAUI DataGrid provides the GroupHeaderStyle (of type Style with target type DataGridGroupHeaderAppearance) configuration which defines the style of the GroupHeader and the aggregates inside the header.

Style the aggregates by using the following properties:

• AggregatesTextColor—Defines the color for the aggregates part of the GroupHeader.
• AggregatesTextFontAttributes—Defines the font attributes for the aggregates part of the GroupHeader.
• AggregatesTextFontFamily—Defines the font family of the aggregates part of the GroupHeader.
• AggregatesTextFontSize—Defines the size of the aggregates part of the GroupHeader.
• AggregatesTextMargin—Defines the margin for the aggregates part of the GroupHeader.

Style the group header by using the following properties:

Style	Action
BackgroundColor	Defines the color that fills the area within the header
BorderColor	Defines the color that fills the border region.
BorderThickness	Defines the thickness of the border.
ButtonFontAttributes	Defines the font attributes for the expand/collapse symbol for the group headers.
ButtonFontFamily	Defines the font family for the expand/collapse symbol of the GroupHeader.
ButtonFontSize	Defines the font size for the expand/collapse symbol of the GroupHeader.
ButtonMargin	Defines the margin for the expand/collapse symbol of the GroupHeader.
ButtonTextColor	Defines the color for the expand/collapse symbol of the GroupHeader.
TextColor	Defines the color for the text part of the GroupHeader
TextFontAttributes	Defines the font attributes for the text part of the GroupHeader.
TextFontFamily	Defines the font family for the text part of the GroupHeader.
TextFontSize	Defines the size for the text part of the GroupHeader.
TextMargin	Defines the margin for the text part of the GroupHeader.

To visualize the GroupHeader, set the ShowGroupHeaderAggregates to True. The property is a property inside the RadDataGrid instance.

Styling the Group Footer

The DataGrid provides the following options for styling its group footer:

• GroupFooterStyle(of type Style with target type DataGridColumnFooterAppearance)—Defines the style of the GroupFooter and the aggregates inside the footer.
• GroupFooterStyleSelector(IStyleSelector)—Defines the style of the selected GroupFooter by passing the GroupFooterContext in the selector.
• FooterStyle(of type Style with target type DataGridColumnFooterAppearance)—Defines the style of the Column Footer and the aggregates inside the Column Footer.

To visualize the GroupFooter, set the ShowGroupFooters property to True. The property is a property inside the RadDataGrid instance.

The following example shows how to define the GroupFooterStyle in XAML:

<Style TargetType="telerik:DataGridGroupFooterAppearance" x:Key="GroupFooterStyle">
    <Setter Property="BorderThickness" Value="0, 1" />
    <Setter Property="BorderColor" Value="BlueViolet" />
    <Setter Property="TextColor" Value="BlueViolet" />
    <Setter Property="TextFontAttributes" Value="Italic" />
</Style>

The following example shows how to use the GroupFooterStyleSelector property:

1. Define the class to which the GroupFooterContext will be passed.

class CustomGroupFooterStyleSelector : IStyleSelector
{
    public Style CustomStyle { get; set; }

    public Style SelectStyle(object item, BindableObject container)
    {
        if (item is GroupFooterContext footerContext
           && footerContext.Group.Key.ToString() == "Video Card"
           && footerContext.Column is DataGridTypedColumn column
           && column.PropertyName == "Quantity")
        {
            return this.CustomStyle;
        }

        return null;
    }
}

2. Define the style selector which will passed to the DataGrid in XAML.

<local:CustomGroupFooterStyleSelector x:Key="GroupFooterStyleSelectorResource">
    <local:CustomGroupFooterStyleSelector.CustomStyle>
        <Style TargetType="telerik:DataGridGroupFooterAppearance">
            <Setter Property="BorderThickness" Value="0, 1" />
            <Setter Property="BorderColor" Value="BlueViolet" />
            <Setter Property="TextFontAttributes" Value="Bold" />
            <Setter Property="VerticalTextAlignment" Value="End" />
        </Style>
    </local:CustomGroupFooterStyleSelector.CustomStyle>
</local:CustomGroupFooterStyleSelector>

Customizing the Group Footer Appearance

Customizing the footer in the DataGrid also changes the appearance of the aggregates inside the component.

The following example demonstrates how to change the style of the column footer aggregates:

1. Define the footer style in XAML.

<Style TargetType="telerik:DataGridColumnFooterAppearance" x:Key="FooterStyle">
    <Setter Property="BorderThickness" Value="0, 1" />
    <Setter Property="BorderColor" Value="PaleVioletRed" />
    <Setter Property="TextColor" Value="PaleVioletRed" />
    <Setter Property="TextFontAttributes" Value="Italic" />
</Style>

2. Add the styling to the DataGrid.

<telerik:RadDataGrid x:Name="dataGrid"
                     AutoGenerateColumns="False"
                     ShowGroupFooters="True"
                     ShowColumnFooters="True"
                     GroupFooterStyleSelector="{StaticResource GroupFooterStyleSelectorResource}"
                     UserGroupMode="Disabled"
                     GroupFooterStyle="{StaticResource GroupFooterStyle}"
                     UserEditMode="Cell">
    <telerik:RadDataGrid.Columns>
        <telerik:DataGridTextColumn PropertyName="Name"
                                    FooterStyle="{StaticResource FooterStyle}">
            <telerik:DataGridTextColumn.AggregateDescriptors>
                <telerik:PropertyAggregateDescriptor PropertyName="Name"
                                                     Function="Count"
                                                     Caption="Total count: " />
            </telerik:DataGridTextColumn.AggregateDescriptors>
        </telerik:DataGridTextColumn>
        <telerik:DataGridNumericalColumn PropertyName="Price"
                                         FooterStyle="{StaticResource FooterStyle}"
                                         CellContentFormat="{}{0:C}">
            <telerik:DataGridNumericalColumn.AggregateDescriptors>
                <telerik:PropertyAggregateDescriptor PropertyName="Price"
                                                     Function="Min" 
                                                     Format="C"
                                                     Caption="Cheapest item: " />
                <telerik:PropertyAggregateDescriptor PropertyName="Price" 
                                                     Function="Max" 
                                                     Format="C"
                                                     Caption="Priciest item: " />
            </telerik:DataGridNumericalColumn.AggregateDescriptors>
        </telerik:DataGridNumericalColumn>
        <telerik:DataGridNumericalColumn PropertyName="DeliveryPrice"
                                         FooterStyle="{StaticResource FooterStyle}"
                                         HeaderText="Delivery Price"
                                         CellContentFormat="{}{0:C}">
            <telerik:DataGridNumericalColumn.AggregateDescriptors>
                <telerik:PropertyAggregateDescriptor PropertyName="DeliveryPrice"
                                                     Function="Average"
                                                     Format="C"
                                                     Caption="Average: " />
            </telerik:DataGridNumericalColumn.AggregateDescriptors>
        </telerik:DataGridNumericalColumn>
        <telerik:DataGridNumericalColumn PropertyName="Quantity"
                                         FooterStyle="{StaticResource FooterStyle}">
            <telerik:DataGridNumericalColumn.AggregateDescriptors>
                <telerik:PropertyAggregateDescriptor PropertyName="Quantity"
                                                     Function="Sum"
                                                     Caption="Total amount: " />
            </telerik:DataGridNumericalColumn.AggregateDescriptors>
        </telerik:DataGridNumericalColumn>
    </telerik:RadDataGrid.Columns>
</telerik:RadDataGrid>

The footer style is added per column.

The following image shows the end result.

See Also

• Property Aggregate Descriptor
• Delegate Aggregate Descriptor