[OpenLayers-Users] Strange. Labels treated as numbers

[Andreas Hocevar]

Christopher Schmidt wrote:
> On Fri, Aug 28, 2009 at 08:52:11AM +0200, Arnd Wippermann wrote:
>   
>> Hi,
>>
>> I want to label features by the attribute name ( label:"${name}" ). The
>> labels should be 06.01, 06.10, 06.080 etc.. But displayed as labels are
>> this: 6.01, 6.1, 6.08.
>>
>> Looking at the code I get no idea, where the place that cause this
>> behaviour. Can someone help.
>>
>> Here is an example of this behaviour:
>> http://gis.ibbeck.de/ginfo/apps/OL27Client/OL28ClientGis.asp?WMC=./data/WMC/
>> strange%20labels.wmc.xml
>>
>> The black and red labels comes from equal attributes. Only the point is
>> changed with a comma.
>>     
>
> Looks like the text is being treated as a number at some point.
> Specifically:
>
> OpenLayers.Style.createLiteral = function(value, context, feature) {
>     if (typeof value == "string" && value.indexOf("${") != -1) {
>         value = OpenLayers.String.format(value, context, [feature]);
>         value = (isNaN(value) || !value) ? value : parseFloat(value);
>     }
>     return value;
> };
>
> Seems like that's slightly overzealous; not sure why we're parseFloating
> the value? (This comes down, to an extent, to OpenLayers not having
> strongly typed data parsing, so we don't know that something should or
> shouldn't be a number.)
>   

The reason is that there are some symbolizer properties that only work
with numbers in IE (e.g. graphicWidth and graphicHeight).

> I'd be in favor of dropping the parseFloat entirely, but I'm not the one
> who put it there :) (Okay, literally speaking, I *did* put it there,
> with my commit in r5429, but I don't think I wrote that code myself.)
>   

In a perfect world, this parseFloat would be done in the renderer, so
this issue deserves a ticket (Arnd, would you be so kind and create one?).

> Andreas, can you explain why this is here? And is it possible we could
> somehow make it optional? 
>   

Why is it there? This code was written at a time where there were no
text labels, so it was easiest to put it there.


Regards,
Andreas.

-- 
Andreas Hocevar
OpenGeo - http://opengeo.org/
Expert service straight from the developers.