[Qgis-developer] Saving expressions

[Bernhard Ströbl]

Hi,

I could imagine having several expressions for one layer (depending on 
the field I want to do calculations on) so autoload needs to depend on 
the layer and the field. On the other hand I could imagine having an 
area field in many layers which I want to update with the geometry's 
area. So a possibility to choose from saved expressions (independent of 
the layer) would come in handy, otherwise I end up copy-pasting the same 
expression from one layer to the other :-(
Besides: Shape files are only one data format. If we save only the 
expressions (last ten, or in a user-defined structure) we can apply them 
to any vector data) or the layer expressions are saved in the project(?)
So Nathan, for me it would be both then :)

just some thoughts...

regards

Bernhard

Am 19.10.2012 07:58, schrieb Paolo Cavallini:
> Il 19/10/2012 07:51, Andreas Neumann ha scritto:
>> For me personally, copy/paste works fine. No need for load and save.
>>
>> I do not fully understand the use case for autoloading (association
>> with a layer). Can you explain why this is desirable? Do you really
>> always want the same expression in all projects for one particular layer?
> I think users will fin useful to have their expression per layer, so
> they can refresh a field with the same calculation, without the need to
> rememberwhich formula they used (very stupi example: refreshing the AREA
> field). In this way, a DBF can be used almost like a spreadsheet.
> For advanced users it is probably useless, for newbies it can save a
> loto of time, effort and frustration remembering which expression they
> used, what is the exact syntax, where (if) they copied the expression
> somewhere, etc.
>
> All the best.
>



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