blazor-devexpress-dot-blazor-dot-dxtreelistsummaryitem.md
Specifies the summary function type.
Namespace : DevExpress.Blazor
Assembly : DevExpress.Blazor.v25.2.dll
NuGet Package : DevExpress.Blazor
[DefaultValue(TreeListSummaryItemType.None)]
[Parameter]
public TreeListSummaryItemType SummaryType { get; set; }
| Type | Default | Description |
|---|---|---|
| TreeListSummaryItemType | None |
An enumeration value.
|
Available values:
| Name | Description |
|---|---|
| Sum |
Calculates the sum of all values in a column.
| | Min |
Calculates the minimum value of all values in a column.
| | Max |
Calculates the maximum value of all values in a column.
| | Count |
Calculates the number of values in a column.
| | Avg |
Calculates the average of all values in a column.
| | Custom |
Uses a custom algorithm to calculate a summary value.
| | None |
Does not calculate a summary value.
|
The Blazor TreeList component can calculate predefined and custom total summaries. For additional information about summaries in the TreeList component, refer to the following topic: Summary in Blazor TreeList.
The TreeList supports the following predefined functions: Sum, Min, Max, Avg, and Count.
Set the FieldName property to the name of a data field whose values are used to calculate the summary.
Count function supports data fields of all types.Min and Max functions support data fields whose values can be compared.Avg and Sum functions require a numeric field.The following example displays predefined summaries for TreeList columns:
@inject EmployeeTaskService EmployeeTaskService
<DxTreeList Data="TreeListData" KeyFieldName="Id" ParentKeyFieldName="ParentId">
<Columns>
<DxTreeListDataColumn FieldName="Name" Caption="Task" />
<DxTreeListDataColumn FieldName="EmployeeName" />
<DxTreeListDataColumn FieldName="StartDate" />
<DxTreeListDataColumn FieldName="DueDate" />
<DxTreeListDataColumn FieldName="Status" Caption="Progress" DisplayFormat="p0" />
</Columns>
<TotalSummary>
<DxTreeListSummaryItem SummaryType="TreeListSummaryItemType.Count" FieldName="Name" />
<DxTreeListSummaryItem SummaryType="TreeListSummaryItemType.Min" FieldName="DueDate" ValueDisplayFormat="y" />
<DxTreeListSummaryItem SummaryType="TreeListSummaryItemType.Max" FieldName="DueDate" ValueDisplayFormat="y" />
<DxTreeListSummaryItem SummaryType="TreeListSummaryItemType.Avg" FieldName="Status" />
</TotalSummary>
</DxTreeList>
@code {
List<EmployeeTask> TreeListData { get; set; }
protected override void OnInitialized() {
TreeListData = EmployeeTaskService.GenerateData();
}
}
public class EmployeeTask {
public int Id { get; set; }
public int ParentId { get; set; }
public string Name { get; set; }
public string EmployeeName { get; set; }
public DateTime StartDate { get; set; }
public DateTime DueDate { get; set; }
public int Progress { get; set; }
public EmployeeTask() { }
public EmployeeTask(
int id,
int parentId,
string name,
string employeeName,
DateTime startDate,
DateTime dueDate,
int progress
)
{
Id = id;
ParentId = parentId;
Name = name;
EmployeeName = employeeName;
StartDate = startDate;
DueDate = dueDate;
Progress = progress;
}
}
public class EmployeeTaskService {
public List<EmployeeTask> GenerateData() {
return new List<EmployeeTask>() {
new EmployeeTask(1, 0, "Simplify & Clarify Product Messaging", "John Heart", new DateTime(2018, 4, 3), new DateTime(2018, 4, 14), 14),
new EmployeeTask(2, 1, "Prepare Financial Reports", "Samantha Bright", new DateTime(2018, 4, 3), new DateTime(2018, 4, 7), 17),
new EmployeeTask(3, 1, "Prepare Marketing Plan", "Arthur Miller", new DateTime(2018, 4, 7), new DateTime(2018, 4, 14), 11),
new EmployeeTask(4, 0, "Create Action Plan to Improve Customer Engagement", "Robert Reagan", new DateTime(2017, 8, 8), new DateTime(2018, 4, 8), 23),
new EmployeeTask(5, 4, "Update Personnel Files", "Greta Sims", new DateTime(2017, 8, 8), new DateTime(2017, 10, 18), 100),
new EmployeeTask(6, 4, "Review Health Insurance Options", "Brett Wade", new DateTime(2017, 9, 27), new DateTime(2017, 11, 10), 37),
new EmployeeTask(7, 4, "Choose Between PPO and HMO Health Plan", "Sandra Johnson", new DateTime(2017, 12, 13), new DateTime(2018, 3, 23), 17),
new EmployeeTask(8, 4, "Update Google Adwords Strategy", "Ed Holmes", new DateTime(2017, 8, 23), new DateTime(2017, 12, 23), 45),
new EmployeeTask(9, 4, "Create New Brochure Design", "Barb Banks", new DateTime(2018, 1, 3), new DateTime(2018, 3, 14), 17),
new EmployeeTask(10, 4, "Obtain Price Quote for New Brochure", "Kevin Carter", new DateTime(2018, 2, 1), new DateTime(2018, 3, 15), 18),
new EmployeeTask(11, 4, "Brochure Design Review", "Cindy Stanwick", new DateTime(2017, 8, 22), new DateTime(2017, 10, 28), 4),
new EmployeeTask(12, 4, "Review Website Redesign Strategy", "Sammy Hill", new DateTime(2017, 9, 16), new DateTime(2018, 3, 6), 73),
new EmployeeTask(13, 4, "Roll Out New Website", "Davey Jones", new DateTime(2017, 11, 7), new DateTime(2018, 2, 6), 9),
new EmployeeTask(14, 4, "Update Sales/Marketing Strategy", "Victor Norris", new DateTime(2017, 12, 13), new DateTime(2018, 4, 2), 5),
new EmployeeTask(15, 4, "Update Sales/Revenue Report", "Mary Stern", new DateTime(2017, 12, 25), new DateTime(2018, 4, 2), 4),
new EmployeeTask(16, 4, "Direct vs Online Sales Comparison Report", "Robin Cosworth", new DateTime(2018, 1, 2), new DateTime(2018, 3, 20), 14),
new EmployeeTask(17, 4, "Review Sales Report and Approve Modifications", "Kelly Rodriguez", new DateTime(2017, 9, 4), new DateTime(2017, 10, 30), 8),
new EmployeeTask(18, 4, "Update R&D Strategy", "James Anderson", new DateTime(2017, 11, 13), new DateTime(2017, 12, 4), 12),
new EmployeeTask(19, 4, "Discuss Updated R&D Strategy", "Antony Remmen", new DateTime(2017, 10, 29), new DateTime(2017, 12, 31), 14),
new EmployeeTask(20, 4, "Update QA Strategy", "Olivia Peyton", new DateTime(2017, 10, 31), new DateTime(2017, 11, 2), 18),
new EmployeeTask(21, 4, "Schedule Training Events", "Taylor Riley", new DateTime(2017, 11, 19), new DateTime(2018, 4, 7), 21),
new EmployeeTask(22, 4, "Approve Hiring of John Jeffers", "Amelia Harper", new DateTime(2018, 1, 7), new DateTime(2018, 4, 8), 10),
new EmployeeTask(23, 0, "Increase Average Subscription Price", "Wally Hobbs", new DateTime(2017, 8, 9), new DateTime(2017, 9, 13), 96),
new EmployeeTask(24, 23, "Update Non-Compete Agreements", "Brad Jameson", new DateTime(2017, 8, 9), new DateTime(2017, 9, 3), 96),
new EmployeeTask(25, 23, "Update Employee Records with New NDA", "Karen Goodson", new DateTime(2017, 8, 23), new DateTime(2018, 9, 10), 100)
};
}
}
// ...
builder.Services.AddSingleton<EmployeeTaskService>();
Set the SummaryType property to Custom to create custom summary items. The following code sample calculates the sum for March Sales values against selected TreeList rows:
@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();
}
}
See Also