Hi Andreas On 26/09/16 16:01, Neumann, Andreas wrote: > > Hi, > > I recently had the need to filter a layer based on a selection, e.g. > for QGIS atlas. The expressions plus plugin provides the > "isselected(layername)" function which returns true|false for each > feature - based on the selection state. > > Could we make this a core expression in QGIS without the need to > install a plugin? I guess this expression is of quite common use for many. >
At the time I implemented this there were no expression variables available and an "expression context" barely existed and therefore a proper solution was out of scope, so it was more suitable to ship it with a plugin than in core. With the current state of expressions it should not be hard to implement it in a clean way. Proposal: isselected(feature, layer_id) <-- explicitly check for a certain feature on a certain layer isselected(feature_id, layer_id) <-- explicitly check for a certain feature on a certain layer isselected() <-- shorthand for the current feature / layer from the expression context. Best regards Matthias _______________________________________________ Qgis-developer mailing list [email protected] List info: http://lists.osgeo.org/mailman/listinfo/qgis-developer Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-developer
