With Swift, how to implement drag and drop

Question

As in Xcode, you connect the user interface elements to blocks of code using ctrl + by dragging and dropping them. Such an operation of dragging and connecting is displayed above the image (see the Blue line with the arrow).

I am working on a very simple macOS application where I have to deal with these types of connections; need a starting point for this.

As follows about this, is there a lib or pod that helps any information would be useful?

Any information on how to draw connector streams and nodes would be helpful?

thanks