I have a simple rule for GUI design: build trees not graphs. Write components that accept a state snapshot and broadcast changes. If component A listens for state changes from B, then A is a parent node of B. If A sends state to B, then A is a parent of B. Components reconcile state before broadcasting changes toward the root of the tree.
Often there is a price paid in brevity, but I believe it is worth it. It may seem annoying to propagate a click explicitly through 5 parent components just to sum clicks into a count widget, but as soon as a short circuit is made, you've created a graph, and you lose the ability to isolate GUI sub-trees for testing/debugging.
Often there is a price paid in brevity, but I believe it is worth it. It may seem annoying to propagate a click explicitly through 5 parent components just to sum clicks into a count widget, but as soon as a short circuit is made, you've created a graph, and you lose the ability to isolate GUI sub-trees for testing/debugging.