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<body><div dir="auto">Hi Stephen,<br>You seem to have fallen in the annotation layer "trap" [0]. There is no layer behind and polygon deletion is mentioned in the docs I pointed to. Basically, select it with the "modify annotations" tool on the same toolbar, and press Del.<br><br>To create regular polygon feature, you have to select the layer, turn it into edit mode and use digitizing tools. Read [1].<br><br>Hope that helps.<br>Harrissou<br><br>[0] <a href="https://docs.qgis.org/3.28/en/docs/user_manual/map_views/map_view.html#interaction">https://docs.qgis.org/3.28/en/docs/user_manual/map_views/map_view.html#interaction</a><br>[1] <a href="https://docs.qgis.org/3.28/en/docs/user_manual/working_with_vector/editing_geometry_attributes.html#digitizing-an-existing-layer">https://docs.qgis.org/3.28/en/docs/user_manual/working_with_vector/editing_geometry_attributes.html#digitizing-an-existing-layer</a></div><br><br><div class="gmail_quote"><div dir="auto">Le 11 juin 2023 01:22:43 GMT+02:00, Stephen Sacks via QGIS-User <qgis-user@lists.osgeo.org> a écrit :</div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<font size="4">My intention was to create a new vector layer
consisting of several polygons. I used the CreatePolygon tool to
mark the four vertices of a rectangle. I must have done something
wrong because I've ended up with a polygon that seems to belong to
no layer. In desperation I ran the following python code, hoping
to delete the mysterious polygon, but it's still there. Are some
layers not in the legend? How do I get rid of the polygon? <br>
========================<br>
from qgis.core import QgsProject<br>
from qgis.utils import iface<br>
<br>
project = QgsProject.instance()<br>
for lyr in project.mapLayers().values(): <br>
lyrName = lyr.name()<br>
print (lyrName)<br>
QgsProject.instance().removeMapLayers([lyr.id()]) <br>
<br>
<br>
<br>
</font>
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