Monitor Firebase information: trigger a function once the document object model has been refreshed

Currently, I am in the process of developing a real-time chat application using Vue.js and Firebase's real-time database.

One specific functionality I am attempting to implement is ensuring that the chat window automatically scrolls to the bottom whenever a new message is received. To accomplish this, I've created a watcher for monitoring changes in the conversation data. However, I'm encountering an issue where the function within the watcher is triggered before the DOM has finished updating, resulting in an incorrect scroll value. I am considering watching another property or finding a way to detect when the new data has been fully loaded into the DOM. Any suggestions on how to tackle this challenge effectively?

Here is the snippet of the HTML code:

<div class="chat" ref="chat">
    <div 
      v-for="(message,key) in conversations" :key="key">
      <div class="message">
        {{message.text}}
      </div>
    </div>
</div>

Here is the script section utilizing VueFire:

const conversations = db.ref('conversations');

export default {
  data() {
    return {
      conversations: {},
    }
  },
  watch: {
    conversations: function() {
      //Scroll to bottom when new message received
      this.$refs.chat.scrollTop = this.$refs.chat.scrollHeight;
    }
  }
}

I have managed to temporarily address this issue by incorporating a timeout, although I personally consider it a bit hacky...

setTimeout(() => {
  this.$refs.chat.scrollTop = this.$refs.chat.scrollHeight;
}, 300);

Your guidance and assistance with resolving this matter would be greatly appreciated. Thank you.

Answer №1

Update: Using MutationObserver instead of DOMNodeInserted

To achieve this, implement a MutationObserver

Check out this functional demo: https://codepen.io/Qumez/pen/WNvOWwp

Develop a method called scrollToBottom:

...
methods: {
        scrollToBottom() {
            this.$refs.wrapper.scrollTop = this.$refs.wrapper.scrollHeight;
        }
    }
...

Invoke the method whenever a new message is appended:

...
data() {
  return {
    mo: {}  
  }
},
mounted() {
        let vm = this;
        this.mo = new MutationObserver((mutationList, observer) => {
            vm.scrollToBottom();
        });
        this.mo.observe(this.$el, {childList: true})
    }
...

Although my variable names differ slightly from yours, they can seamlessly integrate into your existing codebase once updated.

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

What is the best way to single out a specific item from a list to display in a component upon clicking in Vue.js?

To view the data of a specific item in the child component "comandasInd", I just need to click on the icon. <template> <v-data-table :items="comandas"> <template v-slot:items="props"> <td>{{ props.item.nombre }}</td& ...

Retaining filter values when using the Vue.js history back button

Recently, I've been given a project to work on that involves using Vue.js (I'm pretty new to Vue) The project includes creating a page that displays items based on filters set by the user. The user selects the filters and the listing page update ...

Halt the execution of any additional code

I have a favor to ask: Character.count({'character.ownerid': msg.author.id}, function (err, count) { if (err) { throw err; } if (count > 3) { err.message = 'Exceeded character limit'; //create error ...

Steps to trigger an action upon selecting a radio button on an HTML and CSS website

After creating a website with HTML and CSS that allows users to select options using radio buttons, I am now seeking advice on how to implement actions based on their choices. If a user selects an option, I want a specific action to occur, but I am unsur ...

Using Node.js for HTML redirections involves creating routes and setting

I am currently attempting to connect my Node.js API with my HTML pages. For the most part, everything is functioning correctly, but I have encountered some confusion along the way. Is there a more efficient method for redirecting an HTML page? Typically, ...

Can anyone explain why I keep encountering an endless loop when using react hooks?

Having a bit of trouble with fetching data from a JS file that is mimicking an API with some endpoint methods. When I console log the data, everything seems fine, but for some reason, I keep running into an infinite loop when using hooks. I've tried t ...

How can I make Requirejs and Threejs OrbitControls work together?

Having trouble implementing OrbitControls with requirejs. Here's my configuration: I attempted to follow guidance from this post on Stack Overflow RequireJS and THREE.js Orbit Controls, but it's not working. requirejs.config({ baseUrl: &ap ...

Enhance the appearance and format of white space in JavaScript code

I'm in search of a solution to automatically beautify whitespace in my JavaScript code. I have come across tools like JSLint and JSHint that can check for indentation and trailing spaces, but they might not cover all types of whitespace issues. My ch ...

Is it possible to assign two AngularJS modules to a single DOM element simultaneously?

Let's dive into a classic scenario involving portal/CMS widgets: It's uncertain whether or not AngularJS will be present on the page Any number of widgets may or may not exist on the page Each widget could belong to a specific family, with mul ...

Create a layout using CSS that features two columns. The left column should be fluid, expanding to fill all remaining space, while the right column should be fixed

I need to ensure that the Online Users div always remains at a fixed size of 200px, while allowing the chat window next to it to resize dynamically based on available space. Essentially, I want the chat window to adjust its width as the window is resized, ...

Issue with Canvas Update in Loop while Using Three.js Library

In the code snippet provided, it takes in a number of scans which is always set to 2880. The canvas is divided into 2880 sectors to cover a full 360°. The code runs a loop from 0 to 2880, rendering colored points in each sector from the center of the canv ...

Use CSS to position the SVG element to the bottom right corner of the screen

I have a <div> on the page with the CSS class .svgImage applied to it. Whenever I resize the browser window, the svg image resizes correctly but keeps shifting its position on the page. When I make the browser window vertically smaller, the svg imag ...

Issue with Vue.js webpack encountering problems when importing a CSS file from an external library

I'm in the process of integrating the aos animation library into my testing app. I installed it using yarn add aos, and in my Vue application, I've included the following code: <script> .... import AOS from 'aos/dist/aos.js' imp ...

Ways to implement the tabIndex attribute in JSX

As per the guidelines provided in the react documentation, this code snippet is expected to function properly. <div tabIndex="0"></div> However, upon testing it myself, I encountered an issue where the input was not working as intended and ...

What is the best way to conceal a section of a div using CSS/React?

I am attempting to create a design where the entire content of a div is displayed initially, and then after clicking a button labeled "show less", only 300px of the content will be shown with the button changing to "show more". <div className="bod ...

When is the appropriate time to provide arguments to the constructor of a TypeScript service?

I am grappling with the concept of when to pass arguments to a service's constructor versus passing them in the execution of the service. For instance, I have a service that filters rows from an Excel sheet: @Injectable() export class FilterRowsServi ...

The extended interface appears to be lacking the implementation of parent members

I am facing an issue with two interfaces export interface IComponent{ type: ComponentType; name: string; isEnabled:boolean; } export interface IAudioComponent extends IComponent { source: string; volume: number; loop: boolean; ...

JavaScript: Increasing the date by a certain number of days

I've been researching various topics and so far, I haven't come across one that addresses my specific issue. Here's the task at hand: 1) Extract a bill date in the mm/dd/yy format, which is often not today's date. 2) Add a dynamic ...

Exploring Vue 3: Choosing between using import statements in main.js and configuring additionalData in vue.config.js to load a global scss file

I am attempting to load a global SCSS file using the "vue.config.js" file. vue.config.js module.exports = { css: { loaderOptions: { sass: { additionalData: `@import "@/assets/common.scss";` } } } } If I include the style tag in my App. ...

Why does el-select display options in a horizontal manner?

I have recently made the switch from vue.js to vue3 and migrated from using element-ui to element-plus. However, I have encountered a strange issue with the el-select component. The options are being displayed horizontally, like a wrappanel, rather than in ...