Limit Mql5 Draw_Line in Specific Bars

[Ardiansyah]

I have problem with drawing line in custom indicator at the calculation event. 

If i draw a line in only just bar[1] = 20, bar[2] = 10 and [bar[3] = 11, the result is line at bar[0] and other bar up to rates_total is set to 0.0.

double bar[]; //it's indicator buffer

at calculation event:

 bar[1] = 20;

 bar[2] = 10;

 bar[3] = 11;