I am building a plugin using Qt Designer which will initially allow users to select features for a chosen polygon layer and then when a feature is selected on the canvas, the area is printed out in some sort of display widget.
For comparison, the Coordinate Capture tool (shown on the left in the image below) allows users to select on canvas and then print the coordinates in the boxes shown.
How could I connect selecting features on canvas to displaying the area in the text browser?
I am using the following guides for reference:
The following is what I have in code so far. If I move the code from
run(), I can print the total area in the text browser. But can't seem to connect it correctly so that whenever a layer is chosen from the combo box, the text browser get's updated.
def run(self): layers = self.iface.legendInterface().layers() layer_list =  for layer in layers: self.dockwidget.comboBox.clear() self.dockwidget.show() layer_list.append(layer.name()) self.dockwidget.comboBox.addItems(layer_list) selectedLayerIndex = self.dockwidget.comboBox.currentIndex() selectedLayer = layers[selectedLayerIndex] def print_area(self): for feat in selectedLayer.getFeatures(): geom = feat.geometry() self.dockwidget.textBrowser.setText(str(geom.area())) selectedLayerIndex.selectionChanged.connect(run)