treelayout | Demonstrating the importance of laying out data in memory

There are some predicates inside the grammar that contain target specific code (Python in your case). You've picked this grammar:

I added the button to your example, without making it do anything yet. Just, as soon as you hover on a link, the button is shown in the middle of that link, and when you click it, it logs to the console.

Now, there are probably a few things you'll want in the future:

1. Increase the hitbox of the link to make it easier to use;
2. Know which link was clicked, either by writing to a global variable clickedLink, or by re-assigning on('click', ...) inside the on('mouseenter') of the link;
3. Change the data object by adding a new node and calling update either on the entire data set (easy, but computationally expensive) or on the source node and its children.

Just put a border around that simple TextBlock and make sure it stretches horizontally to have the same width as the rest of the node.

JUNG defines a tree as a graph from which there is exactly one path from the (designated) root to any vertex.

A lattice is not a tree, nor is it a forest, so you can't construct the graph you want as a tree/forest; you need to use the general Graph type.

This will also mean that you can't (directly) use TreeLayout on your graph. You can construct a spanning tree of your graph and use TreeLayout on that, but it probably won't look like your diagram above.

Fix your timezone! :

Caused by: com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server time zone value 'Mitteleurop�ische Sommerzeit' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.

Calling Node.collapseTree or Node.expandTree is a relatively low-level operation. Your doubleClick event handler doesn't conduct a transaction (but any change should) nor does it raise any events such as "TreeExpanded" DiagramEvent.

Instead call, CommandHandler.expandTree or CommandHandler.collapseTree. E.g.:

The whole thing is a list of tuples, so loop through. The first item in the tuple is the parent, and the second item is an array of tuples (technically it's a bunch of tuples nested inside each other but I'll assume that's a typo since you never close them).

My previous answer was wrong, I think this should work:

You can declare a type like this