Context

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ReactJS: Zero to Hero
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14
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Context
Overview
DifficultyBeginner
Duration23m
Students49

Description

This module looks at how to manage state in React. You’ll be looking at state management, context, and reducers.  

Learning Objectives 

The objectives of this module are to provide you with an understanding of: 

  • State Management  
  • Context  
  • How to create and provide context  
  • Reducers  
  • How to provide dispatch 

Intended Audience  

This learning path is aimed at all who wish to learn how to use the ReactJS framework.  

Prerequisites

It is essential you understand the face of contemporary web development to attend this course. We insist upon JavaScript experience, along with good HTML and CSS skills. 

Feedback 

We welcome all feedback and suggestions - please contact us at qa.elearningadmin@qa.com to let us know what you think. 

Transcript

The React docs save it, Context provides a way to pass data through the component tree, without having to pass props down manually at every level. So why do we need Context, if we can pass props down? Well, it solves a problem in complex component hierarchies, and it cleans up component code. We've got a simple component tree here that only has two branches and three levels where propX is used in two components on the bottom level. Imagine that we have 10 branches with 30 levels and various components at different levels in the tree, each use propX. That's a lot of extra code because each parent, grandparent, great-grandparent and so on in the tree, must pass propX down, even if it doesn't use the value itself, if one of its children do. Context allows a component high in the tree to provide props to components lower in the tree, without the need to pass props through every component. A provider is needed at the prop source and a consumer at the component that uses it. So what are the use cases for Context? Realistically, there's only one real reason to use Context, and that's why multiple components across multiple trees need to access the same value. So for example, a set of color styles needed in components across an application would be a perfect use case for Context. Note, if you work in a single tree, Context shouldn't really be used to simply bypass components passing props down through them.

Lectures

Introduction to State Management - How to Create and Provide Context - Consume Context - Reducers - Actions in Reducers - The useReducer Hook - Providing Dispatch

About the Author
Students3109
Labs8
Courses29
Learning paths6

An outstanding trainer in software development with more than 15 years experience as a Corporate and Apprentice Trainer, ICT Teacher and Head of Department, with a passion for technology and its uses. Continuing to develop existing and new skills and courses, primarily in web design using PHP, JavaScript, HTML, CSS and SQL but also OOP (Java), programming foundations (Using Python), DevOps (Git, CI/CD, etc) and Agile/Scrum. Practically minded, a quick learner and a problem solver with an attention to detail to ensure high quality outcomes.

Covered Topics