MQL4 Reference Chart Operations ChartRedraw
This function calls a forced redrawing of a specified chart.
void ChartRedraw( long chart_id=0 // Chart ID );
Parameters
chart_id=0
[in] Chart ID. 0 means the current chart.
Note
Usually it is used after changing the object properties.
When the ChartRedraw() function is called from an indicator, the chart is redrawn only after the calculation of the OnCalculate() function is over, because indicators are executed in the common terminal thread.
See also
Objects functions