Unable to get the geometry of temporary layer created from selected features using PyQGIS

Question

I need a temporary layer with the geometry created from selected features for a processing tool. The temporary layer is created but the geometry is missing. The attribute table is blank.

But when I printed the geometry it's showing on console.

Below is the code I am using:

layer = iface.activeLayer() # layer which has a selection 
feat = layer.selectedFeatures()
fields = layer.fields()
selection = QgsVectorLayer('Point', 'temp', 'memory')
dp = selection.dataProvider()
dp.addAttributes(fields)
feats = selection.selectedFeatures()
for feat in feats:
    geom = feat.geometry()
    wkt = geom.asPoint()
print(wkt)
selection.commitChanges()
selection.updateExtents()
QgsProject.instance().addMapLayer(selection)
temp = QgsVectorLayer("D:\satya\cp.shp", "premises", "ogr")

score 5 · Accepted Answer · answered Jan 11 '22 at 07:18

5

You try to select the features in the newly created layer and you use commitChanges without startEditing. addAttributes adds the fields' definition to the target layer. It doesn't add the features' attrribute values.

You can use this script:

layer = iface.activeLayer() # layer which has a selection 
feats = layer.selectedFeatures()
fields = layer.fields()
crs = layer.crs().authid()
selection = QgsVectorLayer('Point?crs=' + crs, 'temp', 'memory')
dp = selection.dataProvider()
dp.addAttributes(fields)
selection.updateFields()
for feat in feats:
    feature = QgsFeature(layer.fields())
    feature.setAttributes(feat.attributes())
    feature.setGeometry(feat.geometry())
    dp.addFeatures([feature])
    dp.updateExtents()
QgsProject.instance().addMapLayer(selection)

answered Jan 11 '22 at 07:18

Kadir Şahbaz

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Thanks Sir, your code is working well. – Satya Dalei Jan 11 '22 at 07:44
Sure, can you please tell me how to save this 'temp layer' to a shapefile. – Satya Dalei Jan 11 '22 at 07:54
Please check this answer. – Kadir Şahbaz Jan 11 '22 at 07:56
Also: https://gis.stackexchange.com/a/325170/29431 and https://gis.stackexchange.com/a/311924/29431 – Kadir Şahbaz Jan 11 '22 at 08:07
exec(open('C:/Users/user/AppData/Local/Temp/tmp0hckdeoh.py'.encode('utf-8')).read()) Traceback (most recent call last): File "C:\PROGRA~1\QGIS31~1.14\apps\Python39\lib\code.py", line 90, in runcode exec(code, self.locals) File "", line 1, in File "", line 20, in TypeError: QgsVectorFileWriter.writeAsVectorFormat(): arguments did not match any overloaded call: overload 1: argument 4 has unexpected type 'NoneType' overload 2: argument 4 has unexpected type 'NoneType' overload 3: argument 3 has unexpected type 'str' – Satya Dalei Jan 11 '22 at 09:25
How to resolve the error?? – Satya Dalei Jan 11 '22 at 09:25
Let us continue this discussion in chat. – Satya Dalei Jan 11 '22 at 11:01

Unable to get the geometry of temporary layer created from selected features using PyQGIS

1 Answers1