TcxDataSummaryItem Class
A summary item.
Declaration
TcxDataSummaryItem = class(
TcxCustomDataSummaryItem
)Remarks
A summary item calculates and displays a summary of a data item according to one of the predefined algorithms in a footer (footer summary) or a data group (group summary).
Main API Members
The list below outlines key members of the TcxDataSummaryItem class. These members allow you to configure common summary item settings.
Summary-Related API Members
- Format
- Specifies a custom formatting pattern for summary display text.
- ItemLink
- Allows you to associate the summary item with a data item.
- Kind
Specifies a predefined summary calculation algorithm.
Tip
You can handle the SummaryItems.OnSummary event to customize or override the selected summary calculation algorithm.
- OnGetText
- Allows you to change the summary item’s display text depending on certain conditions.
- Position
Specifies the summary item position.
You can use this property to position a group summary in the corresponding group panel or group footer.
- Sorted
Specifies if group summary values determine the sort order of data groups.
Note
The Sorted property has no effect on footer summaries.
General-Purpose API Members
- Assign
- Copies compatible settings between summary items.
- BeginUpdate | EndUpdate
- Allow you to avoid excessive summary recalculations and corresponding redraw operations during batch summary item setting changes.
- DataController | DataField
- Provide access to the parent data controller and the source data field in it.
- Index
- Returns the summary item’s index in the parent collection.
- Tag
Allows you to associate the summary item with an integer value to use it as an additional identification mechanism.
Tip
If you assign unique tags to all summary items in the parent collection, you can call its FindByTag function to access summary items by their tags.
- SummaryItems
- Provides access to the parent summary item collection
Indirect TcxDataSummaryItem Class Reference
The TcxDataSummaryItems.Items property references terminal TcxDataSummaryItem class descendants as a TcxDataSummaryItem object.
Terminal TcxDataSummaryItem Class Descendants
The TcxDataSummaryItem class implements common settings for all summary item types. The following terminal descendant classes implement additional settings specific to corresponding controls:
- TcxGridDBTableSummaryItem
- A summary calculated using values of a tabular View’s data field.
- TcxGridServerModeBandedSummaryItem
- TcxGridServerModeSummaryItem
- TcxGridTableSummaryItem
- A column summary.
- TcxTreeListSummaryItem
- A set of appearance and calculation options for a column‘s footer and group summaries.
Related Compiled Demo
To see group and footer summaries in action, run the Grid and Data Editors demo in the VCL Demo Center installed with compiled DevExpress demos. Click Data Summaries or Advanced Data Filtering in the sidebar to select the corresponding VCL Data Grid demo.
Tip
You can find full source code for the installed compiled VCL Data Grid demo in the following folder:
%Public%\Documents\DevExpress VCL Demos\MegaDemos\Product Demos\ExpressQuantumGrid