This chapter has been a fundamental milestone. We built a working geographic rendering module based on rearrangable layers in a LayerGroup, created a MapView widget for interactive displaying of these map renderings, made a visual LayersPane of the layers in our map, and enabled interactive zooming and panning of the MapView.

After following each step, you should now have what looks and feels like a GIS data inspecting application. Of course, a more sophisticated GIS needs additional methods not only to inspect data, but also to manage and edit data—which is what we turn to next.