miliconsult.blogg.se - React redux toolkit

REACT REDUX TOOLKIT CODE

Then, by calling useDispatch as dispatch and passing setColor in our onPress callback, we can send an action to the appropriate reducer case. Grabbing our current state with, we set it as the data entry in our Flatlist element. We import useDispatch and useSelector from React-Redux. The useDispatch hook allows us to dispatch actions. For this, we'll use the useSelector hook, which will give us access to our redux state. Now, all we need is to be able to read the current state in homeScreen.js and dispatch an action to our reducer. We have successfully set up a Redux system for our app.Afterwards, we can import and add the slice to the root reducer of the store. Then an action creator is automatically generated using the name of the reducer as the action type. Here, we set the case functions defined in our reducer to colorSlice.actions. This is because Redux Toolkit allows us to create actions on the fly. Notice that we didn't define any action objects in our code.

REACT REDUX TOOLKIT CODE

But, with createSlice available through Redux Toolkit, we can write mutating code in reducers and have it converted into immutable copies. When writing core Redux logic, it is essential to avoid directly mutating the state value. Note: We can only write mutating code inside the createSlice or createReducer API. In the code block, we take the result of the randomRgb function and add it to the original array of colors.

A reducer function to determine how the state is to be updated.

An initialState value (just like when using the React useState hook).

Importing and calling createSlice in the colorSlice.js file, we define inside it

Next, we'll create a state slice to handle all action and reducer functions relevant to generating a random color in our app.

The store holds a single root reducer object for all the state slices in the app.

The configureStore also automatically sets up the Redux DevTools Extension and some middleware. It uses the configureStore API in place of the createStore API from core Redux to build a store.

We used Redux Toolkit which shortens the length of Redux code logic we have to write in our app.

Inside the HomeScreen.js, we build a simple React-Native application.

Applicationįollowing is an application to generate random colors. Note: This answer is not on React Native and will not focus on React Native concepts.

When multiple components require access to the same piece of state.

When dealing with deeply nested components, passing state and props becomes problematic.

When there's a considerable amount of data changing over time.

This tutorial was just to introduce Redux Toolkit in the most basic way possible. Obviously, the app we just built is too basic to use a global state manager like Redux. Redux can only have a single store in an app. StoreĪ store is an object that holds the app's entire state tree. SliceĪ collection of reducers and actions that work together to implement a single app feature. DispatchĪ function that accepts either a synchronous or asynchronous action object and sends it to a reducer for execution. Reducers don't modify the original state directly rather, they make a copy of the state and modify that. ReducerĪ reducer is a pure function that takes two arguments the current state and an action to return a new state result.

Actions require reducers to be successfully carried out. It is required that actions specify a payload and a type attribute that describes what kind of change is to be made to the state. Redux glossary ActionĪn action is a simple object that indicates a desire to modify a state in the Redux store. The way these are implemented changes when using Redux Toolkit in place of core Redux. To write immutable state updating code.It was designed to simplify the writing of common Redux logic and resolve the usual difficulties of using the core Redux library, such as: Redux Toolkit is Redux's official toolset for developing efficient React-Redux apps.