Thanks, that looks like exactly the kind of function that I'm looking for. I'm using QGIS 2.18.0, I'm wondering, is there any way to use this function without having to select a menu item in the the plugin?
I'm not sure how to get started, because most of the existing plugins seem to be activated by a menu item or a toolbar button in the main editor instead of via the atlas interface. Thank you and I really appreciate the help! On Mon, Dec 12, 2016 at 11:02 PM, Nyall Dawson <[email protected]> wrote: > > > On 13 Dec 2016 4:44 PM, "Shawn Tse" <[email protected]> wrote: > > Hi all, > > I'm interested in being able to make graphs that update depending on > what the active feature in the atlas is. I know some python and a > little bit of the QGIS API, but I'm curious - is there some sort of > listener function for the atlas that gets called whenever the Preview > Atlas/Prev Feature/Next Feature/First Feature/Last Feature buttons are > pressed? > > > Try QgsAtlasComposition::featureChanged. See > https://qgis.org/api/classQgsAtlasComposition.html#ab1a15fdb6d20ebb1254ebb6714254fac > > Nyall > > > What I eventually want to do is to manipulate the node items that were > created in a recent updated version of QGIS, and use them to make a > line graph, gridlines, etc. > > I'm hoping to draw the data directly from the shapefiles themselves or > from a .csv file. > > I originally tried to use an expression in a text box to do this, but > it seems that expressions are unable to use custom functions to > manipulate the composer. So I'm hoping that there's some sort of > Listener method. > > Thanks. > _______________________________________________ > 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 > > _______________________________________________ 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
