While working on a setup wizard that reuses some code from various control-center panels, I noticed that my network list would loose the selection of the  active ap ever so often. After poking at this for a while I realized that you are doing the following:

1. get the current ap
2. get the list of all aps
3. reduce the list to strongest-per-ssid
4. fill the model with the list from 3.
5. select the row which matches the object path of the current ap gotten in 1.

The problem here is that after step 3, the active ap may no longer be in the list (its ssid will still be represented, but the actual object with the same object path may have been filtered out), therefore we don't find it in step 5.

Solution: match by ssid instead of by object path in step 5.