Understanding Vue 3's Reactive Data and Solving the Responsive Problem

Описание: Discover how to effectively manage `Reactive` data in Vue 3 and fix common issues related to responsiveness.
---
This video is based on the question https://stackoverflow.com/q/75911152/ asked by the user 'More' ( https://stackoverflow.com/u/19937973/ ) and on the answer https://stackoverflow.com/a/75911203/ provided by the user 'Dimava' ( https://stackoverflow.com/u/5734961/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: vue3 responsive problem by use reference data

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Solving the Vue 3 Responsive Problem with Reference Data

Vue 3 has brought a host of new features and improvements to the popular framework, making it a top choice for developers. However, a common issue that developers encounter is improperly handling Reactive data, which can lead to problems with responsiveness in your applications. In this post, we’ll break down a scenario involving a Vue 3 application and explain how to fix it to ensure that your data updates correctly on the page.

The Problem: Why Your Page Isn't Updating as Expected

Imagine you have a simple Vue 3 component where you manage an array of locks. The goal is to add random values to this array whenever a button is clicked. However, you noticed that while the first click updates the page correctly, subsequent clicks do not reflect any changes.
Here’s a recap of the issue:

You are using the lock variable to store an array of locks.

On your first button click, you push a random value to the array and update the lock array.

On subsequent clicks, although values are pushed, no updates are shown on the page.

The underlying cause of this problem is rooted in how Vue 3 manages reactive data. When you push values to a non-reactive variable, Vue doesn’t detect the change and therefore does not update the DOM.

Understanding Vue's Reactive Data Structure

To better grasp why this is happening, let’s take a closer look at the Vue 3 Reactive data structure:

Definition: In Vue 3, Reactive refers to objects that Vue observes for changes. When properties of a Reactive object change, Vue automatically updates the DOM to reflect these changes.

First Update: When you first initialize your lock array, it is reactive. You change its value from an empty array ([]) to one containing [1, 2, 3, 4, 5], and Vue correctly re-renders the DOM.

Subsequent Updates: The issue arises when you attempt to perform updates using a reference to a non-reactive variable. When you push values into the array on subsequent clicks, the reference remains the same, and Vue does not register that as a state change.

The Solution: Correctly Updating Reactive Data

To ensure that Vue recognizes changes to your lock array and updates the page accordingly, you need to directly manipulate the reactive lock variable. Here’s how to make the necessary adjustments:

Step-by-Step Instructions

Instead of referencing the non-reactive array (newarr), you should push new values directly into the lock array itself.

Replace the logic in your handleLockData function to look like this:

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

This way, every time you push a new value into the lock.value, Vue detects that the state has changed and the DOM reflects the updated list of locks.

Example Code

Here’s how your complete component might look with the fix applied:

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

Conclusion

In conclusion, managing Reactive data correctly in Vue 3 is essential for ensuring that your application remains functional and responsive. By directly manipulating reactive variables, you can avoid issues where the UI does not update as expected. Always ensure that you’re working with the reactive property itself rather than an isolated copy or reference. This simple change can save you hours of debugging and frustration.

Whether you’re a seasoned Vue developer or just starting out, understanding how to handle reactivity is key to building robust applications. Happy coding!