>>>>May be it's a problem in VFP8 version I'm using, but I can not change the number by typing it in the text portion. It only allows me to type one digit instead of the number.
>>>
>>>
>>>I have no problems with VFP8 also, of course this code will change color at every single keystroke.
>>
>>BTW, does Keyboard input works correctly for you? I can enter any number outside the range and get an error, of course. What's the purpose of KeyboardLowVal/HighVal then?
>
>IAC is fired before the check of the High and Low values, so if you want to be correct in IAC you must add something like:
>

>IF BETWEEN(this.Value, 0, 255)
>   .....
>ENDIF
>

>But I was too lazy to do that :-)

Yes, I was thinking that IC may be firing before internal check for Low/High. If you type the value not in the range, you can not leave the spinner (behaves similar way as invalid date, though I don't see any wait window).

I've added a check to remove the error.