What are actions in Redux Toolkit?

Difficulty: 3/10

createSlice, action creators, reducer logic

In Redux, actions are plain JavaScript objects that describe what event has occurred and how the state should change. Each action must have a type field, and optionally, a payload that carries additional data.

Key Points About Actions

1
Actions are automatically created for each reducer defined inside createSlice().
2
Each action’s type is generated by combining the slice name and reducer name (e.g., counter/increment).
3

Example: Auto-Generated Actions in Redux Toolkit

Scenario Questions

0-2 years experience

1You're adding a toggle feature for a dark mode switch using Redux Toolkit — how would you define and dispatch the action to flip the theme state?
2If you forget to export the action creator from your createSlice and try to use it in a component, what error would you see and why?
3You dispatch an action but the state doesn’t update — what are the two most likely reasons related to actions or reducers?

Follow-up Questions

How do you know if an action was dispatched successfully?
What happens if you dispatch an action that doesn’t match any reducer?
Can you manually create an action without createSlice?