Understanding Events in React: Building an Expense Manager App

This tutorial introduces the concept of events in React by demonstrating how to build a simple Expense Manager application. Below are the main points covered in the tutorial:

Key Concepts

• Events in React: Events in React are similar to events in regular HTML but are named using camelCase and can be passed as functions.
• Handling Events: You can define event handlers to handle user actions like clicks, form submissions, etc.
• State Management: React uses state to keep track of data that can change over time. The Expense Manager app demonstrates managing the state of expenses.

Main Features of the Expense Manager App

• Adding Expenses: Users can input expense details (amount, description, etc.) and submit them.
• Displaying Expenses: The app dynamically displays a list of added expenses.
• Deleting Expenses: Users can remove expenses from the list.

Example Code Snippet

Here's a basic example of how events are handled in the Expense Manager app:

class ExpenseManager extends React.Component {
    constructor(props) {
        super(props);
        this.state = {
            expenses: [],
            amount: '',
            description: ''
        };
    }

    handleAmountChange = (event) => {
        this.setState({ amount: event.target.value });
    }

    handleDescriptionChange = (event) => {
        this.setState({ description: event.target.value });
    }

    handleSubmit = (event) => {
        event.preventDefault();
        const newExpense = {
            amount: this.state.amount,
            description: this.state.description
        };
        this.setState(prevState => ({
            expenses: [...prevState.expenses, newExpense],
            amount: '',
            description: ''
        }));
    }

    render() {
        return (
            
                
                    
                    
                    Add Expense
                
                
                    {this.state.expenses.map((expense, index) => (
                        {expense.description}: ${expense.amount}
                    ))}
                
            
        );
    }
}

Conclusion

The tutorial provides a clear and practical understanding of how to implement events in React applications by building an Expense Manager app. Beginners can learn how to manage user input, handle events, and maintain state effectively in React.