Exercise 08 - Spawning Actors

You’ve made it to the final exercise! 🎉 We’ll learn how to distribute state in localized, private little entities called actors.

Goals

• Learn how to spawn() actors dynamically and see how this can be helpful in isolating logic and state
• In timerAppMachine.js, spawn a new timer machine via createTimerMachine() on the ADD action.
• Update the context via assign() so that it has the updated context.timers (with the newly spawned timer appended) and context.currentTimer (with the index of that timer).

Overall, a sample user flow should look like this:

1. User sees the <NewTimer> screen
2. User enters a number (greater than 0)
3. User presses the enter key or clicks the Play button
4. Now, the <Timer> screen shows with the user’s specified duration
5. That timer should be immediately started.
6. When the user presses the Delete button, we should:
   • Go to the previous timer, if there are any.
   • Otherwise, go back to the <NewTimer> screen.
7. When the user presses the Add button, we should go to the <NewTimer> screen to add a new timer.
   • If the user presses the Cancel button on this screen, we should go back to the previous timer.