To my great consternation, route transition animations broke after upgrading the app – when going from one section to another, the old one was visible behind the new one until the transition was finished, and it looked terrible. I could not think what could be the problem.

Then, out of the blue (well, after breaking my head on it for a while), it hit me – I didn’t have any material!

(A bit of background – in the material design system, everything is based on material, which is inspired by how things work in the real world.

  1. Imagine a sheet of paper.
  2. Now, cut a button from another piece of paper.
  3. Put the button on the first sheet.

Now you have a button, which is made from material, on top of the rest of your design, which is also a piece of material.)

The routing had been based on MaterialApp. With the update, it used Navigator instead. MaterialApp gives you some material to fall back on – it is, after all, a material app. Navigator – not so much. In upgrading, I had dropped the material that the whole app was built on!

Lesson learned: when you’re growing, don’t lose your roots.

Between one level and the next, before he can reach the higher one, he is in a state of decline from his previous level…
This is considered a decline only relative to his former state, and not (G‑d forbid) relative to all other men; for he still surpasses them in his divine service…
For the mainstay of his service while he is in this fallen state is the love of G‑d in which he had been educated and trained from his youth

Rabbi Shneur Zalman of Liadi, “The Alter Rebbe”, Tanya, Chinuch Katan