exclusive choice

[Chris Baron]

Hi,
this is for a Browsergame i'am playing in an ally.
We're programming a report tool to keep the ally-mates better informed about ones combats.

Ok, it's about a village where a combat took place:
the village always has one troup of the defender and none, one or two support troups.
The troups are grouped by tribes.

The "reporter" has 3 selectboxes, where he has to pick the tribes of the participants from.
The choices have to be exclusive. If the defender e.g. has Romans, support 1 + 2 must not have them.
If defender=germans and support1=gauls and there is a support2, support2 has to be roman.
The selectboxes will have the following names and keys-value-pairs:
Defender

0=Please Select

1=Romans

2=Germans

3=Gauls

Support1

0=Please Select

1=Romans

2=Germans

3=Gauls

Support2

0=Please Select

1=Romans

2=Germans

3=Gauls

The tool will validate the input with JavaScript, but this doesn't matter here.
It's rather about the puzzle, how to solve the validation with the shortest, firmest code
cb
[ February 19, 2005: Message edited by: Chris Baron ]

[Rachel Swailes]

What about instead of validating after the user's selection - limit the selection that the user can make. For example, if he selects Gauls in defender then remove Gauls from the other selection boxes.

[Chris Baron]

Hi Rachel,
i had this idea too, but gave it up, because it's very confusing if one wants to change the selections. I have an "onChange" validation with an array at the moment. Simplified:

var selectedYet = Array();
...
var value = selectBox.value; // e.g. 1
var role  = selectBox.name;  // e.g. Defender
var tribe = selectBox.options[value].text; // e.g. Romans
 
if( selectedYet[tribe] == null )
    selectedYet[tribe] = role;  
else 
    alert( tribe + " are selected for " + selectedYet[tribe] + " yet" );

It's working fine, but i wonder how to solve this mathematically.
cb
[ February 23, 2005: Message edited by: Chris Baron ]

[Eugene Lucash]

I wandering, who needs a mathematical model when solution is simple enouph in terms of object manipulation and behaviours?

[Warren Dew]

A variant on Rachel's suggestion: disable the radio buttons rather than making them disappear entirely.

Or maybe that's what Rachel meant.