given is a layer with some nodes on it and every node has some attributes(name, id, etc...). For showing up the informations of a single node I can use the "Identify Feature Tool". Choose the tool, click the node and see the informations. I am trying to develop a Plugin with Python, which is doing almost the same: Start the Plugin, click on a node and get the informations about this node(output in the python console is enough for the first steps). Okay, so this is the status: I was following this tutorial: http://www.qgisworkshop.org/html/workshop/plugins_tutorial.html which works not for QGIS 2.0. The 'MouseClickEvent' is working, I get the X,Y-coordinates. But I am not able to select and to get the informations of a node. That is my selectFeature function, which is called by result = QObject.connect(self.clickTool, SIGNAL("canvasClicked(const QgsPoint &, Qt::MouseButton)"), self.selectFeature):

def selectFeature(self, point, button):
    #pntGeom = QgsGeometry.fromPoint(point)
    #pntBuff = pntGeom.buffer( (self.canvas.mapUnitsPerPixel() * 2),0) 
    #rect = pntBuff.boundingBox()

    layer = self.canvas.currentLayer()
    selected_features = layer.selectedFeatures()
    for i in selected_features:
        attrs = i.attributeMap()
        for (k,attr) in attrs.iteritems():
            print "%d: %s" % (k, attr.toString())

This let me see nothing. I was reading and trying out a lot of things and at the moment in feel a bit lost. I lost the overview.

Do I need these geometry functions to capture the node by clicking the mouse button?

What functions do I need to get the attributes of a single selected feature?

1 Answer 1


You aren't selecting anything in your code. Once you have the point click coordinates, you need to select features using:

QgsVectorLayer.select (QgsRectangle, False)

In other words, create a QgsRectangle around the click point using whatever search radius you want and then select the feature(s):

# use 5 map units for selecting
radius = 5
rect = QgsRectangle(point.x() - radius,
                    point.y() - radius,
                    point.x() + radius,
                    point.y() + radius)
layer.select(rect, False)
# process selected features

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.