TdxSpreadSheetTableViewSelection.BeginUpdate Method

Postpones all selection change notifications and worksheet redraw operations until an EndUpdate call.

Declaration

procedure BeginUpdate;

Remarks

A spreadsheet control redraws its active worksheet every time a selection state change occurs. Enclose multiple selection state changes between the BeginUpdate and EndUpdate procedure calls to avoid excessive redraw operations.

The following code example selects three non-adjacent cell ranges as a single operation:

Delphi

var
  ATableView: TdxSpreadSheetTableView;
begin
  ATableView := dxSpreadSheet1.ActiveSheetAsTable;
  // Stops selection state updates
  ATableView.Selection.BeginUpdate;
  // Selects the first cell range (B2:D4)
  ATableView.Selection.Add(Rect(1, 1, 3, 3));
  // Selects the second cell range (B6:D8)
  ATableView.Selection.Add(Rect(1, 5, 3, 7), [ssCtrl]);
  // Selects the last cell range (B10:D13) and moves focus to the C12 cell
  ATableView.Selection.Add(Rect(1, 9, 3, 12), [ssCtrl], 11, 2);
  // Resumes selection state updates and applies all the changes
  ATableView.Selection.EndUpdate;
end;

C++

  TdxSpreadSheetTableView *ATableView;
  ATableView = dxSpreadSheet1->ActiveSheetAsTable;
  // Stops selection state updates
  ATableView->Selection->BeginUpdate();
  // Selects the first cell range (B2:D4)
  ATableView->Selection->Add(Rect(1, 1, 3, 3));
  // Selects the second cell range (B6:D8)
  ATableView->Selection->Add(Rect(1, 5, 3, 7), TShiftState() << ssCtrl);
  // Selects the last cell range (B10:D13) and moves focus to the C12 cell
  ATableView->Selection->Add(Rect(1, 9, 3, 12), TShiftState() << ssCtrl, 11, 2);
  // Resumes selection state updates and applies all the changes
  ATableView->Selection->EndUpdate();

Important

Ensure that an EndUpdate call follows every BeginUpdate procedure call, even if an exception occurs.