How to Properly Call Functions Between Files in React Functional Components

Discover how to easily pass and call functions from a main file to functional components in React Native, simplifying your app structure and enhancing performance.
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Calling Functions in React Functional Components

As you transition from class components to functional components in React Native, you might encounter a few challenges. One common issue developers face is calling functions defined in the main file from a functional component. This post will walk you through a clear and effective solution to this problem, ensuring smoother refactor and actions between components.

The Problem

After refactoring an application from class components to functional components, a developer discovered difficulties in accessing and executing functions across different files:

In the Home.js file, several state management hooks and functions (start, stop, reset) were defined.

The StartStopButtons component had its logic in a separate Button.js file and needed to access these functions for button presses.

Before the refactor, this.state.start and this.state.stop methods were readily accessible within the class. However, in functional components, they need to be passed as props to maintain the connection.

The Solution

Step 1: Pass Functions as Props

You can easily pass your functions from the main file (Home.js) to the StartStopButtons component, just like you do with state variables. Here’s how you can modify your Home.js file for this purpose:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Adjust the StartStopButtons Component

Next, you need to ensure that the StartStopButtons component is set up to accept these new props. Here’s how your Button.js can be structured:

[[See Video to Reveal this Text or Code Snippet]]

Summary

By following these steps, you pass your functions as props to the StartStopButtons component just like you do with your state variables. This allows the buttons to call the functions defined in Home.js, facilitating smooth component interaction without losing functionality during your transition to functional components.

Utilizing proper prop passing not only simplifies your code but greatly enhances the maintainability of your React Native app. Embrace the power of functional components, and don’t hesitate to refactor your code to improve clarity and functionality.