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<p>Hi developers,</p>
<p>I am developing a Python processing algorithm with some child
algorithms. I am struggling to find a way to access a child
algorithm's output vector layer. I want to use
isChildAlgorithm=True in order to correctly set the feedback
progress.<br>
</p>
<p>* If I use processing.run(...) with setting the parameter
isChildAlgorithm to False (= default), the vector layer (via sink)
is returned as a QgsVectorLayer.<br>
* If I set isChildAlgorithm to True, only the dest_id is returned
as a string. I did not find a solution on how I retrieve the
corresponding QgsVectorLayer.<br>
* Is it intentional that the vector layer is returned as
QgsVectorLayer or str (dest_id), depending on the isChildAlgorithm
parameter?<br>
* How can I access output QgsVectorLayer from a child algorithm?<br>
</p>
<p>This is a minimum example where you can modify the
is_child_algorithm parameter:</p>
<p>parameters = {<br>
'INPUT': QgsVectorLayer('Point?crs=epsg:31258', 'locations',
"memory"),<br>
'DISTANCE': 10,<br>
'OUTPUT': 'TEMPORARY_OUTPUT'<br>
}<br>
result = processing.run("native:buffer", parameters,
is_child_algorithm=False )<br>
vector_layer = result['OUTPUT']<br>
print(str(type(vector_layer)))</p>
<p>Best regards<br>
Simon<br>
</p>
<pre class="moz-signature" cols="72">--
Simon Gröchenig MSc
MTA - Mobility & Transport Analytics
Salzburg Research Forschungsgesellschaft mbH
Jakob-Haringer-Straße 5/3 | 5020 Salzburg, Austria
T: +43.662.2288-314
<a class="moz-txt-link-abbreviated" href="mailto:simon.groechenig@salzburgresearch.at">simon.groechenig@salzburgresearch.at</a>
<a class="moz-txt-link-freetext" href="http://www.salzburgresearch.at">http://www.salzburgresearch.at</a></pre>
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