[Qgis-developer] undisplayed elements are selected

[Andreas Neumann]

 For me it would be ok if I can select invisible features from the 
 table, but it feels strange to select invisible features in the map.

 After all my filter is there for a reason - I want them to be invisible 
 and therefore I don't want them to be selectable if they are invisible. 
 QGIS server with GetFeatureInfo behaves like this and I think it is 
 logical.

 It even gets more complicated if you digitize and have snapping 
 settings on a rule-based layer. Think about it - you digitize and 
 suddenly it snaps to some invisible feature - it would be a usability 
 nightmare ...

 Andreas

 On Fri, 16 Mar 2012 09:40:37 +0100,  wrote:
> some thoughts (unordered):
>
> A) thinking from the table side I can always select any feature there
> regardless if it is currently visible or not. When I zoom to the
> selection then I am responsible that all features are visible in 
> order
> to see my selection. So the current behaviour is just the other way
> round. If I want to exclude features I have to define a query on the
> layer filtering out unwanted features.
>
> B) map visibility can be controlled by three ways:
> 1) visibility of the layer on/off => features are not selectable in 
> map
> 2) scale-based visibility of the whole layer => features get
> selected, even when not visible
> 3) rule based style with scale based visibility for rules (Denis'
> case) => features get selected, even when not visible
> To me case 1 is expected behaviour, cases 2 and 3 are not (although
> not too unexpected when considering thought A), but hard to explain 
> to
> a user)
>
> - possible solution to accompany A) and B): show all selected
> features in selection color regardless of their individual 
> scale-based
> visibility. No idea if that is feasible.
>
> Bernhard
>
> Am 16.03.2012 09:12, schrieb Andreas Neumann:
>> hm - I agree with Denis. Features invisible because of scale ranges
>> should not be selectable and should not react to map tips.
>>
>> In QGIS Server we filtered the invisible features away in 
>> GetFeatureInfo
>> requests. The same should be done for selecting features in QGIS 
>> desktop
>> and for the map tips. The rule-based renderer V2 offers a method 
>> called
>> willRenderFeature() (see
>> 
>> http://doc.qgis.org/api/classQgsRuleBasedRendererV2.html#b514bc63bd9e744faca24236a89b7e4d)
>> that could be used to see if such a feature is displayed or not. But 
>> the
>> method says that it has to be called between startRender() and
>> stopRender() calls - so I don't know if it would work for
>> querying/selection features?
>>
>> Any thoughts?
>> Andreas
>>
>> On Fri, 16 Mar 2012 00:44:02 -0700, Nathan Woodrow wrote:
>>> I would say this could be an expected behaviour as styling is only 
>>> a
>>> visual thing and doesn't affect the data....maybe.
>>>
>>> - Nathan
>>>
>>> Sent from my Windows Phone
>>> From: Denis Rouzaud
>>> Sent: 16/03/2012 5:20 PM
>>> To: Qgis-developer at lists.osgeo.org
>>> Subject: [Qgis-developer] undisplayed elements are selected
>>> Hi all,
>>>
>>> When using the rules style for a layer and defining a scale range, 
>>> if
>>> you select by rectangle on the map, everything is selected 
>>> including
>>> undisplayed features.
>>>
>>> Is there already an issue opened, I searched without any result.
>>>
>>> Greetings,
>>>
>>> Denis
>>> _______________________________________________
>>> Qgis-developer mailing list
>>> Qgis-developer at lists.osgeo.org
>>> http://lists.osgeo.org/mailman/listinfo/qgis-developer
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>>> http://lists.osgeo.org/mailman/listinfo/qgis-developer
>>
>
>
>
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 Andreas Neumann
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