kDevelop 4.7.0 parsing WxWidgets projects

[Steve the Fiddle]

I am trying to use kDevelop 4.7.0 on Debian 8 to work on a large
project built with WxWidgets 2.8.12.
Because Debian Stable now uses WxWidgets 3.0, I have built WxWidgets
2.8.12 from source, and then configured the project (Audacity 2.1.1
alpha) with:
./configure --enable-debug
WX_CONFIG=/home/myusername/sourcecode/wxGTK-2.8.12/buildgtk/wx-config

The project builds successfully.

The problem is that it seems that kDevelop cannot find WxWidgets, so
it complains about all Wx functions saying "Declaration not found" and
prompting me to declare the function.

How do I tell kDevelop where to find WxWidgets so that it can parse
the code correctly in the editor window?

Steve