# creates two features with the add feature tool
layer = qgis.utils.iface.activeLayer()


# manual interaction !
# select the first feature with the "select features be rectangle"-tool and then do the following line:
featId1 = layer.selectedFeaturesIds()[0]

# add values  to the first feature
for i in range(5):
    layer.changeAttributeValue(featId1, i, (i*10))

# manual interaction !
# select the second feature with the "select features be rectangle"-tool and then do the following line:
featId2 = layer.selectedFeaturesIds()[0]

# changes the geometry of the second feature
newGeom = QgsGeometry.fromPolyline([QgsPoint(1,1), QgsPoint(2,2)])
layer.changeGeometry(featId2, newGeom)
qgis.utils.iface.mapCanvas().refresh ()

# add values  to the second feature
for i in range(5):
    layer.changeAttributeValue(featId2, i, (i*10 + 1000))


# get the second feature by using featureAtId...    
feat = QgsFeature()
layer.featureAtId(featId2, feat, True, True)

# print values from the second feature
for i in range(5):
    print feat[i].toString()

# for some reason the attributeValues to the first feature get printed out. 
# in the attribute table it looks correct. 
# feat.geometry().asPolyline() seems to return the right geometry
# if I save edits after creating the two new features it works as it should