Skip to main content

DevExpress v24.2 Update — Your Feedback Matters

Our What's New in v24.2 webpage includes product-specific surveys. Your response to our survey questions will help us measure product satisfaction for features released in this major update and help us refine our plans for our next major release.

Take the survey Not interested

TdxGanttControlTaskStartMoveEvent Type

Allows you to prevent a task drag-and-drop operation within the chart.

#Declaration

Delphi
TdxGanttControlTaskStartMoveEvent = 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 moved.

AAllow Boolean

If True, a user can drag and drop tasks in the chart. If False, the operation is prohibited.

#Remarks

You can open the Features Demo and modify its code. Handle the OnTaskStartMove event and use the following code snippet to forbid the move operation for summary tasks and milestones:

procedure TFeaturesDemoMainForm.GanttControlViewChartTaskStartMove(Sender: TObject;
  ATask: TdxGanttControlTask; var AAllow: Boolean);
begin
  AAllow := not (ATask.Summary or ATask.Milestone);
end;
See Also