[Qgis-user] automatically reload (csv) file

[Dr. Marco Lechner]

Hi Nicola,

I guess this will only redraw the features in the mapcanvas, but not
necessarily read the datasource file, but I'm not sure about this.

Marco

Am 18.09.2015 um 10:02 schrieb Nicola Poles:
> To reload a CSV file you can press the Refresh button on the toolbar or
> press the "F5" key
> 
> Nicola
> 
> On Fri, Sep 18, 2015 at 9:16 AM, Dr. Marco Lechner <mlechner at bfs.de
> <mailto:mlechner at bfs.de>> wrote:
> 
>     Hi,
> 
>     how (often) does QGIS read features from a file (like csv or shape -
>     differences?)? I realize I do not really know how the datasource - qgis-
>     communication goes.
> 
>     Imaine you have a csv or shape file that is loaded into QGIS but is
>     automatically replaced from time to time (or lets say externally
>     edited). Using a database- instead of file-based approach is better for
>     sure, but still it is not clear when / how often (on which events) QGIS
>     requests features from the datasources.
> 
>     As an idea in mind I see, the nice Sync-Plugin
>     (https://plugins.qgis.org/plugins/SyncQGISWithDir/) can monitor folders
>     and notify the user if a new layer is available in a folder (well it
>     does not take care of a changed layer (new timestamp of file, but adding
>     this functionality should not be such a big thing). The user could also
>     be notified when a layers file changed.
> 
>     But I'm not sure what was the best way to implement the (re)loading of
>     an already loaded layer. Do I have to drop the layer and reload it
>     (including keeping the style) or is there a more efficient way?
> 
>     Marco
> 
>     --
>     Dr. Marco Lechner
>     Bundesamt fuer Strahlenschutz / Federal Office for Radiation Protection
>     SW2.1 Koordination Notfallschutzsysteme / Coordination Emergency Systems
>     Rosastrasse 9 | D-79098 Freiburg | Germany
>     mlechner at bfs.de <mailto:mlechner at bfs.de> | +49 (0)3018 333 6724
>     <tel:%2B49%20%280%293018%20333%206724> | www.bfs.de <http://www.bfs.de>
> 
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