[Qgis-developer] Issue with creating new feature

[Alexander Bruy]

Hi all,

during plugin update to new vector API I found some strange
behaviour with creating new features in vector layer/file writer.
There is nice description about how to retrieve features and
attributes from existing vector layer, but I can't find any
information about creating new ones.

Here is my test code for Python console:

>>>from PyQt4.QtCore import *
>>>fields = QgsFields()
>>>fields.append(QgsField("id", QVariant.Int, "", 20))
>>>fields.append(QgsField("value", QVariant.String, "", 255))
>>>fields.append(QgsField("area", QVariant.Double, "", 20, 6))
>>>fields.append(QgsField("perim", QVariant.Double, "", 20, 6))
>>>w = QgsVectorFileWriter("/home/alex/test.shp", "utf-8", fields, >>>QGis.WKBPolygon, None)
>>>f = QgsFeature()
>>>f.setAttribute("id", QVariant(0))
False
>>>f.setAttribute(0, QVariant(0))
False

It is impossible to add attribute by its name or index. In API docs
I found method setFields() that used to "assign a field map with
the feature to allow attribute access by attribute name". But when
I assign field map to feature

>>>f.setFields(fields)

and try to add attribute again by name or id I get crash
(stacktrace attached).

It is possible to set all attributes at once using

>>>f.setAttributes([QVariant(0), QVariant("text"), QVariant(2.3), QVariant(100.456)])

Is this correct or maybe I miss something?

Thanks
-- 
Alexander Bruy
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