labelingpyqgisqgis-3
In QGIS 2.18 I read and set label style settings like this:
props = {
"labeling": "pal",
"labeling/enabled": "true",
"labeling/fontFamily": "Arial",
"labeling/fontSize": "12",
"labeling/fieldName": "Name",
"labeling/bufferDraw": True,
"labeling/bufferSize": "1",
"labeling/bufferColor": "white"
}
for k, v in props.items():
my_layer.setCustomProperty(k, v)
How do I do the equivalent in QGIS 3.0?
Try adjusting/editing the text properties. Try increasing the leading values. It's always set to zero as default. Set it to 1 or 2 and see what happens. I have not used Maplex engine for some time however; when labelling normally I often use "Leading" in the text properties because it nicely separates stacked text. (Layer Properties/Symbol/Formatted Text)
In the maplex label engine, there might be something you can change for the Stack Label. You have it set to default... try playing with switching the settings.
After having a look at your CSV data file I have to say that the field names you are handling are not really recommended, since they generate all sorts of problems.
When you stated your question I guessed your field names looked like "Top\nElevation", which is not the case if you look at your data file, since it contains field names in the form:
"Top
Elevation"
and that is certainly different.
As you have acknowledged, a fieldIndex should be enough to overcome those weird field names, but the fieldIndex is not implemented if you look at the QGIS code.
My Answer
I suggest you to implement a workaround.
I understand you need field names like those you have, mainly for presentation purposes. So, why not setting a multi-line alias for those fields and leaving your original field names in one line?
How to do that?
Change your CSV field names to something like this (concatenate the multiple words with an underscore "_" ):
Right click on the layer Grid and select Properties.
Go to the menu Fields and in the row corresponding to the "Top_Elevation" field, edit the alias value.
Write TopElevation. As you can notice any ENTER you press won't start a new line. To insert the new line character you can open a text editor, press ENTER and then select and copy the character created (you need to have faith to do this :D).
With such a magic character in your clipboard, edit the alias again and paste the character between Top and Elevation. It will seem that you just entered a space, but you need to keep the faith :D.
Finally, click on OK to close the dialog. This is how my dialog looks like before I click on OK:
And this is the result running your plugin (see the fields in the attribute table, the one which we defined an alias on is a multi-line field name):
This way you will be able to set a label on all your fields. In case that you have troubles with the code, I'm pasting you the following code snippet for reference:
valLabel=QgsPalLayerSettings()
valLabel.readFromLayer(iface.activeLayer())
field = iface.activeLayer().dataProvider().fields()[6].name()
valLabel.fieldName = field
valLabel.writeToLayer(iface.activeLayer())
iface.mapCanvas().refresh()
Best Answer
I found the answer for QGIS 3.0: