Creating vector layer (Shapefile) with QgsNewVectorLayerDialog

Question

I'm using the following code that displays a window to create a new Shapefile:

from qgis.gui import QgsNewVectorLayerDialog

new_vector_layer_dialog = QgsNewVectorLayerDialog()
new_vector_layer_dialog.show()

How can I put a flag on the Polygon by code, and not the line or the point?

Also when you press the OK button, how to get the dialog to select where to save the Shapefile?

When you click OK, it does not create a Shapefile, but just closes the dialog box. Additionally, it does not create a vector layer in the Layers Panel.

What do I need to do to create the layer and load it into the Layers Panel?

Answer 1

You need to call the static method runAndCreateLayer instead of show:

from qgis.gui import QgsNewVectorLayerDialog

layerPath = QgsNewVectorLayerDialog().runAndCreateLayer()
if layerPath:
    layer = QgsVectorLayer(layerPath, 'new layer', 'ogr')
    QgsMapLayerRegistry.instance().addMapLayer(layer)

---

Concerning the Polygon radio button, the dialog doesn't seem to let you do that. You could do something like this:

myDialog.findChild( QRadioButton, 'mPolygonRadioButton').setChecked(True)

Which will be nonetheless overwritten when calling runAndCreateLayer.

Note: The QgsNewVectorLayerDialog class for QGIS 3 lets you set a CRS. Setting geometry type could be a feature request for QGIS.