Setting name of output layer PyQGIS

Question

The script below is to merge number of layers in a specific group, the output layer name is Merged. How can I change the name? I tried to change the output parameters but it's not working.

root = QgsProject.instance().layerTreeRoot()
group = root.findGroup("RL")
layers = [layer.layer()
for layer in group.children()] 
merged = processing.run("native:mergevectorlayers",\
{'LAYERS': layers, 'OUTPUT':"TEMPORARY_OUTPUT"})["OUTPUT"]
QgsProject.instance().addMapLayer(merged, False)
root.insertLayer(0, merged)
root = QgsProject.instance().layerTreeRoot()
group = root.findGroup("SL")
layers = [layer.layer()
for layer in group.children()]
merged = processing.run("native:mergevectorlayers",

{'LAYERS': layers, 'OUTPUT':"TEMPORARY_OUTPUT"})["OUTPUT"]
QgsProject.instance().addMapLayer(merged, False)
root.insertLayer(0, merged)

Just a tip, you don't need to use line endings ; with Python — Matt, Jan 23 '22 at 12:11

score 5 · Answer 1 · edited Jan 23 '22 at 17:25

5

You can use the QgsMapLayer.setName() function. Based on your script, you can do something along the lines of:

merged.setName("This is the new layer name")

edited Jan 23 '22 at 17:25

Jacqueline

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answered Jan 23 '22 at 10:54

fastest

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I write it at the end of the script but it gives me error – Ahmed Kamel Jan 23 '22 at 11:02
What is the error message? Otherwise, I would suggest to put the command right after you have executed the processing algorithm (i.e., before calling addMapLayer()) – fastest Jan 23 '22 at 11:05
what is the error? it works. – Jacqueline Jan 23 '22 at 16:39

I tried this and it's working

blockLayer = QgsProject.instance().mapLayersByName("Merged")[0]
blockLayer.setName("SL Dozers")

– Ahmed Kamel Jan 23 '22 at 16:54

MortenSickel · Answer 2 · 2022-01-23T21:10:26.943

2

In a comment you said "I tried this and it's working"

blockLayer = QgsProject.instance().mapLayersByName("Merged")[0] 
blockLayer.setName("SL Dozers")

This may not work if there should be more than one layer with the same name in your project. See my answer to a similar question for a failsafe way: https://gis.stackexchange.com/a/352267/10123

output = processing.run("native:mergevectorlayers",\
{'LAYERS': layers, 'OUTPUT':"TEMPORARY_OUTPUT"})["OUTPUT"]
createdlayer = QgsProject.instance().mapLayer(output)
createdlayer.setName('My shiny new beautiful layer')

(Explanation: What is returned by the algorithm is a dictionary where you can find an id for the layer, then you can get and rename the layer using the unique id rather than the name)

edited Jan 23 '22 at 21:10

answered Jan 23 '22 at 19:30

MortenSickel

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there is an error with "parmas" in the first line you typed – Ahmed Kamel Jan 23 '22 at 20:17
That is just whatever parameters you put onto the function, I rewrote it to use your example, hope this works – MortenSickel Jan 23 '22 at 21:00

Setting name of output layer PyQGIS

2 Answers2