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TdxGanttControlTaskStartDragEvent Type

Performs a set of actions before a user moves a task in the sheet.

#Declaration

Delphi
TdxGanttControlTaskStartDragEvent = procedure(Sender: TObject; ATask: TdxGanttControlTask; var AAllow: Boolean) of object;

#Parameters

Name Type Description
Sender TObject

The Chart View that raised the event.

ATask TdxGanttControlTask

The task that is about to be rearranged.

AAllow Boolean

If True, a user can rearrange a task row in the sheet with the mouse. If False, the operation is prohibited.

#Remarks

You can open the Features Demo and modify its code. The code snippet below shows how you can handle the OnTaskStartDrag event to prevent a user from task rearrangement:

procedure TFeaturesDemoMainForm.GanttControlViewChartOptionsSheetTaskStartDrag(
  Sender: TObject; ATask: TdxGanttControlTask; var Allow: Boolean);
begin
  inherited;
  Allow := not ATask.Summary;
end; 
See Also