TdxCustomGaugeControl.CancelUpdate Method

Enables updating a Gauge Control instance after the BeginUpdate method is called.

Declaration

procedure CancelUpdate;

Remarks

This procedure re-enables control repainting without invalidation. If you need to change several properties and/or visual elements within the ExpressGauge control, flickering may occur. If the BeginUpdate method is invoked, any changes in the control are not visualized until the EndUpdate is called. The BeginUpdate/EndUpdate pair of methods must enclose the code updating the gauge control. Every call of the BeginUpdate method increments the internal counter by one. Every call of the EndUpdate or CancelUpdate method decrements this counter by one. The gauge control can refresh itself only when the internal counter is 0.

The EndUpdate method also triggers gauge control invalidation. If no changes are made, you can call the CancelUpdate method instead to allow further updates of the control. Unlike EndUpdate, the CancelUpdate method does not invalidate the gauge control. If you call the CancelUpdate method after performing changes affecting the ExpressGauge control’s appearance, an exception will occur.