vcl-dxganttcontrolviewchart-f9a00aca.md
Performs a set of actions before a user changes task progress with a mouse drag-and-drop operation.
TdxGanttControlTaskPercentCompleteStartChangeEvent = procedure(Sender: TObject; ATask: TdxGanttControlTask; var AAllow: Boolean) of object;
| 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.
|
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;
void __fastcall TFeaturesDemoMainForm::GanttControlViewChartPercentCompleteStartChange(TObject *Sender,
TdxGanttControlTask *ATask, bool &AAllow)
{
AAllow = !(ATask->Summary);
}
See Also
TdxGanttControlTaskPercentCompleteChangeEvent