[Qgis-user] PyQGIS: Get project extent outside QGIS

[Jorge Gustavo Rocha]

Hi,

Answer to my own question: the order was wrong.

I need to call

QgsLayerTreeMapCanvasBridge

before reading the project.

This works:

QgsApplication.setPrefixPath("/usr", True)
qgs = QgsApplication([], False)
# Load providers
qgs.initQgis()

project = QgsProject.instance()

root = project.layerTreeRoot()
canvas = QgsMapCanvas()

bridge = QgsLayerTreeMapCanvasBridge(root, canvas)

project.read(projectpath)

print(project.crs().authid())

print(canvas.extent())
print(canvas.fullExtent())
print(canvas.mapSettings().extent())
print(canvas.mapSettings().fullExtent())
print(canvas.mapSettings().visibleExtent())

Sorry for the noise.

Jorge

On 18/11/19 16:55, Jorge Gustavo Rocha wrote:
>
> Hi,
>
> I want to read a project file and get the extent when the project was
> saved.
>
> In QGIS,
>
> iface.mapCanvas().extent()
>
> does exactly what I want. But I want to run a script outside QGIS.
>
> I've already tried:
>
> QgsApplication.setPrefixPath("/usr", True)
> qgs = QgsApplication([], False)
> # Load providers
> qgs.initQgis()
>
> project = QgsProject.instance()
> project.read(projectpath)
>
> print(project.crs().authid())
>
> root = project.layerTreeRoot()
> canvas = QgsMapCanvas()
>
> bridge = QgsLayerTreeMapCanvasBridge(root, canvas)
>
> print(canvas.extent())
> print(canvas.fullExtent())
> print(canvas.mapSettings().extent())
> print(canvas.mapSettings().fullExtent())
> print(canvas.mapSettings().visibleExtent())
>
> All of these extents are much wider than the canvas extent when the
> project was saved.
>
> The extent is there, in the project file. I can read it as XML and get
> the extent.
>
>   <mapcanvas annotationsVisible="1" name="theMapCanvas">
>     <units>meters</units>
>     <extent>
>       <xmin>-22630.49319827121144044</xmin>
>       <ymin>208610.29666395089589059</ymin>
>       <xmax>-22314.35674389618725399</xmax>
>       <ymax>208889.62023152899928391</ymax>
>     </extent>
>
> But I would like to use the API.
>
> Thanks in advance,
>
> Jorge
>
> -- 
> Email Signature
> Logo <https://www.geomaster.pt> 	
> *Geomaster*
> *Jorge Gustavo Rocha* | Software Engineer
> *e:*jgr at geomaster.pt | *m:*+351 910 333 888
> *g:*41.54094,-8.40490 | *v: *510 906 109
> *a: * Rua António Cândido Pinto, 67, 4715-400 Braga
>
>
> _______________________________________________
> Qgis-user mailing list
> Qgis-user at lists.osgeo.org
> List info: https://lists.osgeo.org/mailman/listinfo/qgis-user
> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
-- 
Email Signature
Logo <https://www.geomaster.pt> 	
*Geomaster*
*Jorge Gustavo Rocha* | Software Engineer
*e:*jgr at geomaster.pt | *m:*+351 910 333 888
*g:*41.54094,-8.40490 | *v: *510 906 109
*a: * Rua António Cândido Pinto, 67, 4715-400 Braga

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-user/attachments/20191118/618e7db1/attachment.html>