Sets the focus the control with the number given. Number is the control number where 1 is the first control that appears, 2 the second and so on. This can be useful in validating use input. E.g.,
:SCREEN BOBTEST
MODVAR,"Var 1",50,50,20,10,
BUTTON,"OK",20,90,0,0,C,,SPECIAL>SETFOCUS|1&IFTHENELSE&TEST>TVar 1=0&\
BRANCH>OK&SPECIAL>STOP|Var 1 must be even integer!
BRANCH,"OK",0,0,0,0,,,,OTHERSCR
(where Tvar 1 = INITIAL(MODULO(Var 1,2)) ~ ~ | ).
