The trick is to never recreate the grid.

Select whatever into cursor curtemp && a temp cursor
select mycursor && The cursor that drives your grid
zap
select from (dbf('curtemp'))
yourgrid.refresh()

>Hi all,
>I have a form with one Grid on it.
>When I move on Table1 records, I want to create a cursor ( MyCursor ) and fill it with some data from Table2.
>I put below code in MyRefillGrid method.
>
>In Init method :
>

>CrsTempSabt = "_" + SUBSTR(SYS(2015), 4)
>

>
>In MyRefillGrid method :
>
>

>CREATE CURSOR &MyCursor  (HCode C(14), HName C(100), HADesc C(50), Hnum1 N(12,0), Hnum2 N(12,0))
>
>
>* Filling MyCursor with Table2 data
>
>
>thisform.grid1.RecordSource = MyCursor
>thisform.grid1.column1.ControlSource = "HCode"
>thisform.grid1.column2.ControlSource = "HName"
>thisform.grid1.column3.ControlSource = "HADesc"
>
>SELECT &MyCursor
>GO TOP
>Thisform.grid1.Refresh
>

>
>It is ok for first time that I run my form, but when I move to another record in table1, and want to recreate MyCursor, all of grid columns destroyed ( column width and also its header title )
>What must I do? I dont want to create MyCursor once and delete all record in MyCursor each time. i want to have a clear cursor.
>Thanks