Developing a Task Management App with Next.js: Implementing Context API and Interfaces

In this tutorial, we will learn how to create Context API and Interfaces in Next.js while building a Task Management App. Context API is a way to manage global state in React applications and Interfaces are used to define the shape of the data that is passed around in the application. Next.js is a React framework that allows us to build server-side rendered and static websites.

Step 1: Setting up the Next.js project
First, let’s create a new Next.js project. Open your terminal and run the following commands:

npx create-next-app task-management-app
cd task-management-app

Step 2: Creating the Context API
Next, let’s create a new file called TaskContext.js in the context folder of our project. Inside this file, we will define our Context API.

import { createContext, useReducer } from 'react';

const initialState = {
  tasks: []
};

const TaskContext = createContext(initialState);

const taskReducer = (state, action) => {
  switch (action.type) {
    case 'ADD_TASK':
      return {
        ...state,
        tasks: [...state.tasks, action.payload]
      };
    case 'DELETE_TASK':
      return {
        ...state,
        tasks: state.tasks.filter(task => task.id !== action.payload)
      };
    default:
      return state;
  }
};

const TaskProvider = ({ children }) => {
  const [state, dispatch] = useReducer(taskReducer, initialState);

  return (
    <TaskContext.Provider value={{ state, dispatch }}>
      {children}
    </TaskContext.Provider>
  );
};

export { TaskContext, TaskProvider };

Step 3: Using the Context API in our components
Now that we have created our Context API, let’s use it in our components. In our pages/index.js file, we will import our TaskProvider component and wrap our main component with it.

import { TaskProvider } from '../context/TaskContext';

const Home = () => {
  return (
    <TaskProvider>
      {/* Your main component here */}
    </TaskProvider>
  );
};

export default Home;

Step 4: Creating Interfaces
Next, let’s create a new file called TaskInterface.js in the interfaces folder of our project. Inside this file, we will define our Task interface.

export interface Task {
  id: number;
  title: string;
  description: string;
  completed: boolean;
}

Step 5: Using Interfaces in our components
Now that we have created our Task interface, let’s use it in our components. In our pages/index.js file, we will import our Task interface and use it to define our state.

import { TaskContext } from '../context/TaskContext';
import { Task } from '../interfaces/TaskInterface';

const Home = () => {
  const { state, dispatch } = useContext(TaskContext);

  const [tasks, setTasks] = useState<Task[]>(state.tasks);

  // Your component logic here
};

Step 6: Building the Task Management App
With our Context API and Interfaces set up, we can now start building our Task Management App. You can create components for adding tasks, deleting tasks, marking tasks as completed, etc. Remember to use the Context API to manage the state of your tasks and the Interfaces to define the shape of your data.

That’s it! You have now learned how to create Context API and Interfaces in Next.js while building a Task Management App. Happy coding!