[Qgis-developer] Labeling: data-defined fields shifted after new vector API?

Larry Shaffer larrys at dakotacarto.com
Wed Jan 30 17:42:13 PST 2013


Hi,

On Mon, Jan 28, 2013 at 6:17 AM, Régis Haubourg <
regis.haubourg at eau-adour-garonne.fr> wrote:

> martin Dobias wrote
> > I have briefly looked into the code and it seems that new labeling
> >> stores data-defined attributes by index instead of name. If so,
> >> that's
> >> the source of the problem and it should be changed to read/write
> >> names
>
> Hi all,
> +1 for switching storage of data defined fields with names and not indexes.
> It was a limit I previously pointed and this is really weak if data field
> order change. But we need retrocompatibility with old projects.  Does that
> sounds possible?
> régis
>

So, is anyone working on this? I can devote some time this coming weekend.
Pretty important to fix this, then make it compatible with < 2.0 projects.

Similarly, data defined properties are only a 1-to-1 relationship
(currently property-to-field index), with no defined relationship between
themselves, the QgsPalLayerSettings (if any) to override, the associated
QgsField, any defined QgsExpression, or any assigned 'buddy' gui elements.
Nathan suggested a data binding class that could possibly be inherited by
gui classes to make utilizing data defined overrides (not just for
labeling) within the app easier and more abstracted. I think it is worth
pursuing.

On another note (and yet a bunch more refactoring), most of the
QgsPalLayerSettings are directly accessed public properties. These should
probably be switched over to some form of container object (QMap?) no?

Regards,

Larry



> --
> View this message in context:
> http://osgeo-org.1560.n6.nabble.com/Labeling-data-defined-fields-shifted-after-new-vector-API-tp5030238p5030276.html
> Sent from the Quantum GIS - Developer mailing list archive at Nabble.com.
> _______________________________________________
> Qgis-developer mailing list
> Qgis-developer at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/qgis-developer
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-developer/attachments/20130130/d6f497da/attachment.html>


More information about the Qgis-developer mailing list