Skip to main content
All docs
V24.2

DevExpress v24.2 Update — Your Feedback Matters

Our What's New in v24.2 webpage includes product-specific surveys. Your response to our survey questions will help us measure product satisfaction for features released in this major update and help us refine our plans for our next major release.

Take the survey Not interested

DxTreeList.RefreshSummary() Method

Refreshes all total summary values in the TreeList.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v24.2.dll

NuGet Package: DevExpress.Blazor

#Declaration

C#
public void RefreshSummary()

#Remarks

Call the RefreshSummary method to update custom summary values that change dynamically.

In the following code snippet, the TreeList’s custom summary displays the sum of March Sales values for selected TreeList rows. The RefreshSummary method updates the custom summary value when a user selects new rows.

Run Demo: Custom Summary

Razor
@inject ISalesByRegionDataProvider SalesByRegionDataProvider
<DxTreeList @ref="TreeList"
            Data="Data"
            KeyFieldName="ID"
            ParentKeyFieldName="RegionID"
            ShowAllRows="true"
            CustomSummary="TreeList_CustomSummary"
            CustomizeSummaryDisplayText="TreeList_CustomizeSummaryDisplayText"
            SelectedDataItemsChanged="TreeList_SelectedDataItemsChanged">
    <Columns>
        <DxTreeListSelectionColumn Width="50px" />
        <DxTreeListDataColumn FieldName="Region" Width="15%" />
        <DxTreeListDataColumn FieldName="MarchSales" DisplayFormat="c0" Width="25%" />
        <DxTreeListDataColumn FieldName="SeptemberSales" DisplayFormat="c0" Width="15%" />
        <DxTreeListDataColumn FieldName="MarchChange" DisplayFormat="p2" Width="15%" />
        <DxTreeListDataColumn FieldName="SeptemberChange" DisplayFormat="p2" Width="15%" />
        <DxTreeListDataColumn FieldName="MarketShare" DisplayFormat="p0" Width="15%" />
    </Columns>
    <TotalSummary>
        <DxTreeListSummaryItem SummaryType="TreeListSummaryItemType.Count" FieldName="Region" />
        <DxTreeListSummaryItem SummaryType="TreeListSummaryItemType.Sum" FieldName="MarchSales" />
        <DxTreeListSummaryItem SummaryType="TreeListSummaryItemType.Custom" FieldName="MarchSales" Name="Custom" />
    </TotalSummary>
</DxTreeList>

@code {
    ITreeList TreeList { get; set; }
    object Data { get; set; }
    protected override void OnInitialized() {
        Data = SalesByRegionDataProvider.GenerateData();
    }
    void TreeList_CustomSummary(TreeListCustomSummaryEventArgs e) {
        switch(e.SummaryStage) {
            case TreeListCustomSummaryStage.Start:
                e.TotalValue = 0m;
                break;
            case TreeListCustomSummaryStage.Calculate:
                if(e.TreeList.IsDataItemSelected(e.DataItem))
                    e.TotalValue = (decimal)e.TotalValue + (decimal)e.GetRowValue("MarchSales");
                break;
        }
    }
    void TreeList_CustomizeSummaryDisplayText(TreeListCustomizeSummaryDisplayTextEventArgs e) {
        if(e.Item.Name == "Custom")
            e.DisplayText = string.Format("Sum of Selected ({0}): {1:c0}", e.TreeList.SelectedDataItems.Count, e.Value);
    }
    void TreeList_SelectedDataItemsChanged(IReadOnlyList<object> newSelection) {
        TreeList.RefreshSummary();
    }
}

Blazor TreeList - Summary for Selection

For more information about summaries in the TreeList component, refer to the following topic: Summary in Blazor TreeList.

See Also