Parts and Connections Tree

The parts tree and connections tree are loaded from two XML files. 

Inside your TinkerCell folder, take a look at PartsTree/PartsTree.xml  and PartsTree/ConnectionsTree.xml

The PartItems folder contains the files to draw each part. The PartsTree/Icons folder contains the icons for each part. 

To add a new item to the tree, just edit the xml file. If you do not provide an icon and/or a PartGraphicsItem with the same name, then the item will automatically get the same icon and graphics as its parent.