Folding

This step shows how to enable collapsing and expanding of group nodes. This is provided through class FoldingManager and its support classes.

GraphEditorInputMode provides the following default gestures for collapse/expand:

Press Alt + LeftArrow or click the expand-button on the node's top left corner to close (collapse) an open group node.
Press Alt + RightArrow or click the collapse-button on the node's top left corner to open (expand) a closed group node.
Press Alt + DownArrow to enter (navigate into) a group node.
Press Alt + UpArrow to exit (navigate out of) a group node.

See the sources for details.