TcxSummaryEventArguments.RecordIndex Field

Stores the index of the currently processed record.

Declaration

RecordIndex: Integer

Field Value

Type	Description
Integer	The index of the currently processed record.

Remarks

You can use the RecordIndex field to identify the source record in the parent data controller.

Code Example

All predefined summary calculation algorithms use record values of only one data item. The OnSummary event allows you to modify a predefined summary calculation algorithm in any manner. For example, you can use values of multiple data items in every iteration of the summary calculation process.

The code example below demonstrates an OnSummary event handler that modifies the predefined algorithm MAX. The event handler calculates the highest population density based on data-aware grid columns that display country areas (DBTableView1Area) and corresponding population values (DBTableView1Population):

Delphi

procedure TMyForm.cxGrid1DBTableView1DataControllerSummaryDefaultGroupSummaryItemsSummary(
  ASender: TcxDataSummaryItems; Arguments: TcxSummaryEventArguments;
  var OutArguments: TcxSummaryEventOutArguments);
var
  AArea, APopulation: Variant;
begin
  // Obtain the area value for the currently processed record
  AArea := ASender.DataController.Values[Arguments.RecordIndex, DBTableView1Area.Index];
  // Obtain the population value for the currently processed record
  APopulation := ASender.DataController.Values[Arguments.RecordIndex, DBTableView1Population.Index];
  OutArguments.Value := APopulation/AArea; // Calculates the custom summary value (maximum population density)
end;

C++

void __fastcall TMyForm::cxGrid1DBTableView1DataControllerSummaryDefaultGroupSummaryItemsSummary(
  TcxDataSummaryItems *ASender, TcxSummaryEventArguments &Arguments,
  TcxSummaryEventOutArguments &OutArguments) {
  // Obtain the area value for the currently processed record
  Variant AArea = ASender->DataController->Values[Arguments.RecordIndex][DBTableView1Area->Index];
  // Obtain the population value for the currently processed record
  Variant APopulation = ASender->DataController->Values[Arguments.RecordIndex][DBTableView1Area->Index];
  OutArguments.Value = APopulation/AArea;  // Calculates the custom summary value (maximum population density)
}