GridColumnSummary.Type Property

Gets or sets the aggregate function type.

Namespace: DevExpress.XamarinForms.DataGrid

Assembly: DevExpress.XamarinForms.Grid.dll

NuGet Package: DevExpress.XamarinForms.Grid

Declaration

[XtraSerializableProperty]
public SummaryType Type { get; set; }

Property Value

Type	Description
SummaryType	A SummaryType enumeration value that specifies the aggregate function type.

Available values:

Name	Description
None	Disables summary value calculation.
Sum	The sum of all values in a column.
Min	The minimum value in a column.
Max	The maximum value in a column.
Count	The record count.
Average	The average value of a column.
Custom	Specifies whether data summaries should be calculated according to a custom rule specified in the DataGridView.CalculateCustomSummary event handler.

Remarks

Use the Type property to specify the aggregate function that should be used to calculate the summary value. There are five predefined aggregate functions for grid data summaries: Sum, Min, Max, Average and Count.

To implement and apply a custom aggregate function, set the Type property to Custom and handle the DataGridView.CalculateCustomSummary event.

Example

This example demonstrates how to use predefined aggregate functions and custom rule to calculate group and total summaries for grid columns.

• Set the group summary to display the maximum Total value for each group of records.
• Set the total summary to calculate the sum of values in the Total column.
• Set the custom total summary to count the number of orders whose value in the Shipped column is false (to count orders that are not shipped).

XAML

<dxg:DataGridView x:Name="grid" ItemsSource="{Binding Orders}" 
                 CalculateCustomSummary="OnCalculateCustomSummary">
    <!-- ... -->
    <dxg:DataGridView.GroupSummaries>
        <dxg:GridColumnSummary FieldName="Total" Type="Max"/>
    </dxg:DataGridView.GroupSummaries>

    <dxg:DataGridView.TotalSummaries>
        <dxg:GridColumnSummary FieldName="Total" Type="Sum" 
                               DisplayFormat="Total: {0:C0}"/>
        <dxg:GridColumnSummary FieldName="Shipped" Type="Custom" 
                               DisplayFormat="Not Shipped: {0}"/>
    </dxg:DataGridView.TotalSummaries>
</dxg:DataGridView>

C#

int count;
// ...

void OnCalculateCustomSummary(object sender, CustomSummaryEventArgs e) {
    if (e.FieldName.ToString () == "Shipped")
        if (e.IsTotalSummary){
            if (e.SummaryProcess == CustomSummaryProcess.Start) {
                count = 0;
            }
            if (e.SummaryProcess == CustomSummaryProcess.Calculate) {
                if (!(bool)e.FieldValue)
                    count++;
                e.TotalValue = count;
            }
        }
}