3

I'm trying to change attribute values in a memory layer. My memory layer is defined in this way:

pro.addAttributes([QgsField("nom", QVariant.String), QgsField("valeur", QVariant.Int)])

I made several tries:

attrs = { 0 : "hello"}
bFlag3=vl.dataProvider().changeAttributeValues({ fet.id() : attrs })

Or in this way :

bFlag3=vl.changeAttributeValue(fet.id(),0,'hello')

Each time my boolean flag returns True but I never see any change in my memory table. I make a

vl.commitChanges()

in both cases.

When I try these two pieces of code on the two other layers (which aren't memory layers...) I have in my project, I see the attributes change...

Can anyone help me troubleshoot this?

  • In fact i just noticed that i'm not able to (manually) modify the fields of this (programmatically created) memory layer in QGIS interface ... Any hint ? – snaileater Aug 7 '14 at 12:35
0

Your code seems correct, but you are missing one line of code:

  vl.updateFields()   

This is not necessary when you edit a layer and then closes it, as it will show correctly when you load it again, but it is necessary if you want to use/see it in the same session.

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