362321 - XUL decks assume the selectedIndex attribute has been set

Status: NEW

(Toolkit :: UI Widgets, defect)

Description

[Alex Vincent [:WeirdAl]]

If the XUL author hasn't set a selectedIndex attribute and later tries to set it to 0 (the number), the check for (this.getAttribute == val) returns true.  This isn't nice.

Per discussion on #developers, changing val to String(val) seems a good solution.

Comment 1

[[e-mail]]

Maybe the getter should return || "0" ?

Comment 2

[Daniel Kirsch]

Maybe I don't really understand the problem here. The property should always return an integer. If no attribute was explicitly set it should return 0. Using getAttribute you always get a string. While this is usually clear to a developer the current situation is not.

In current builds the deck returns a string for the selectedIndex property. While I usually assume to get an integer from such a property and the documentation at http://developer.mozilla.org/en/docs/XUL:deck and http://www.xulplanet.com/references/elemref/ref_deck.html#prop_selectedIndex says it's an integer this is pretty irritating.

My following script to toggle a deck's view doesn't work because of that:

 var deck = document.getElementById("propertiesDeck");
 deck.selectedIndex = (deck.selectedIndex+1)%2;

as "deck.selectedIndex+1" is always becomming "11" instead of 2.

My current workaround is to convert the selectedIndex property to an int.

 deck.selectedIndex = (parseInt(deck.selectedIndex)+1)%2;

Either documentation should be fixes or the property should return an integer (which I think is the much better solution).

Comment 3

[Daniel Kirsch]

(In reply to comment #2)
> My current workaround is to convert the selectedIndex property to an int.
> 
>  deck.selectedIndex = (parseInt(deck.selectedIndex)+1)%2;

This should read:

 deck.selectedIndex = (parseInt(deck.selectedIndex||0)+1)%2;

Otherwise the first change never happens because selectedIndex returns an empty string and parseInt("") returns NaN.