Before we can make use of our new Highlighter class, we need to import it:

from highlighter import Highlighter

We now simply need an instance of it, which we will pass to our TextArea instance and the path to a YAML file. Since we only have one YAML file currently, we will just hard-code the path to it. In the next chapter, we will add the ability to load different YAML files:

self.highlighter = Highlighter(self.text_area, 'languages/python.yaml')

That's all we need to do to get syntax highlighting into our TextArea, since the Highlighter class will bind to events in our TextArea and cause it to update itself.

With syntax highlighting complete, the next item on our agenda is to fix the line numbers. We will again split this into a new class to keep things organized.

Create a file in the same directory called linenumbers.py, ready for this class.