TBM_SETPOS Overview Group

The TBM_SETPOS message sets the current logical position of the slider in a trackbar.

TBM_SETPOS 

wParam = (WPARAM) (BOOL) fPosition; 

lParam = (LPARAM) (LONG) lPosition;

Parameters

fPosition: Redraw flag. If this parameter is TRUE, the message redraws the control with the slider at the position given by lPosition. If this parameter is FALSE, the message does not redraw the slider at the new position. Note that the message sets the value of the slider position (as returned by the TBM_GETPOS message) regardless of the fPosition parameter.
lPosition: New logical position of the slider. Valid logical positions are the integer values in the trackbar's range of minimum to maximum slider positions. If this value is outside the control's maximum and minimum range, the position is set to the maximum or minimum value.

No return value.