for a vector-layer I would like to produce an action, that shows the changed value in a formular.

E.G. I am editing a vector-point-layer, click on a point, the fomular is opening. I change a value (lets say the formular-field "z" had a value "test" and I change it to "test2").

Then I start my developed action.

I tried for example:

from qgis.PyQt import QtWidgets

QtWidgets.QMessageBox.information(None, "Feature id", "feature id is [
$z ] '%Z%' '%z%' $z [z] $Z [Z] [%z%] [%Z%]")

but I always get the "old" value "test" and not the formular-changed value "test2".

Has anybody an idea what I can do?

  • Did you save your modifications before trigger your action ? – Sociabilis May 27 '19 at 12:30
  • No, I did not. I try to find a solution where I can find the changed values in the form before they are saved. – Kai Behncke May 27 '19 at 12:45

I found a solution. Not by an action but by a specific formular:

from qgis.PyQt.QtWidgets import QWidget,QLineEdit,QPushButton,QDialogButtonBox
from PyQt5.QtCore import *
from PyQt5.QtGui import *

def my_form_open(dialog, layer, feature):
    geom = feature.geometry()
    control = dialog.findChild(QLineEdit, "z")
    #layer = qgis.utils.iface.activeLayer()
    global myDialog
    myDialog = dialog
    global myFeature
    myFeature= feature
    buttonBox = dialog.findChild(QDialogButtonBox,"buttonBox")
    #Wire up our own signals.
    # Wire up our own signals.

def validate():

    qgis.utils.iface.messageBar().pushMessage("Autosave", u"Validalli : ")
    layer = qgis.utils.iface.activeLayer()
    #qgis.utils.iface.messageBar().pushMessage("Autosave", u"blba : "+z.text())
    z = myDialog.findChild(QLineEdit, "z")
    myFeature['z'] = z.text()


If s.o. wants to add a new feature it`s important in ther validate-section: activeLayer.startEditing() activeLayer.addFeature(myFeature)


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