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TdxGanttControlTaskPercentCompleteStartChangeEvent Type

Performs a set of actions before a user changes task progress with a mouse drag-and-drop operation.

#Declaration

Delphi
TdxGanttControlTaskPercentCompleteStartChangeEvent = 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 whose progress is about to be changed.

AAllow Boolean

If True, a user can move the mouse pointer to the left or right over the task’s bar (while holding down the left mouse button) to change the progress percentage. If False, the operation is prohibited.

#Remarks

You can open the Features Demo and modify its code. Handle the OnPercentCompleteStartChange event and use the following code snippet to forbid the progress change operation for summary tasks:

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