List skip one row

[ajenat]

Hello..
In VFP9, if we press downarrow just when/before creating the list box, the second item is skipped and third item is selected.
SET TALK OFF
clear
DIMENSION myarray(6)
myarray(1)='Ashwani Khurana'
myarray(2)='Aditya Pasricha'
myarray(3)='Arjuna Panday'
myarray(4)='Dalip Kumar'
myarray(5)='Komaljit Kaur'
myarray(6)='Naresh Gupta'
STORE 1 TO my1list,my2list
@2,2 SAY 'my1list'
@2,36 say'my2list'
@15,1 say'Press <TAB> and <DownArrow> as quickly as you can to minimise delay between them.'
@3,1 get my1list from myarray
READ
@16,1 say'In my2list Selection will reach at 3rd item instead of 2nd.'
@3,35 get my2list from myarray
READ time 1
IF my2list=3
@17,1 say'See you press downarrow once but 2nd item skipped.' colo RGB(255,0,0,255,255,255)
else
@17,1 say'Oops, try again.' colo RGB(255,0,0,255,255,255)
ENDIF
* Behaviour remains same in Forms.

 

[Chris Miller]

Instead of using the TAG property, you could also define a listbox class that has a "LastListIndex" integer properrty and keep track how that sometimes changes by 2 or more to correct it to only skip by 1.

Define Class _Listbox as Listbox
    LastListIndex = 0

    Procedure ProgrammaticChange()
       This.LastListIndex = This.Listindex
    EndProc

    Procedure InteractiveChange()
       #Define DNARROW 24
       #Define UPARROW 5
       Do Case 
          Case Lastkey()=DNARROW And This.Listindex>This.LastListIndex+1
             This.Listindex = Min(This.Listcount,This.LastListIndex+1)
          Case Lastkey()=UPARROW And This.Listindex<This.LastListIndex-1
             This.Listindex = Max(1,This.LastListIndex-1)       
       EndCase
       This.LastListIndex = This.Listindex
   EndProc
EndDefine

Don't use this as a class definition in a PR, redo that as visual ListBox class in a VCX, add the property LastListIndex and the code ofthe two change events. You can also make the constants part of a header file which you can set to be used for the whole class, though for the moment you only need the constants in the InteractiveCahnge event.

Chriss