This package provides a Flutter widget that allows you to display interactive force directed graphs. The widget can be updated (to add or remove nodes/edges for example) and can animate between states. Nodes can optionally be dragged by the user or pinned. The package comes with an implementation of the Fruchterman Reingold algorithm but you can substitute a different algorithm if desired. See the example for usage.
Check out a demo at https://jonaird.github.io/force_directed_graph/