Many time we have use case to add child/grand child component on main component. If we found any error in life cycle events (e.g. connectedCallback, renderedCallback) of child or grand child component, that error should we shown on parent component instead of respective child component. In lightning web component has excellent feature errorCallback which creates a error boundary.
This error boundary captures all errors from its descendent component tree for life cycle events. It will not capture any other events issue like button click handler issue. We can log and show life cycle event error based on our application design.
Sample Code to handle life cycle error
errorCallback handler should be put in parent or container components. This will help us in getting all errors from child or grand child components. We can show errors in UI based on our UI design.
Here is parent or container component code which will catch all child component errors.
Child Component:
Let us take example, we want to include external data library in our component. That external js file should be loaded using renderedCallback. If any error will be thrown while loading js it will catched by parent container.
Here is error which will be thrown by childModule component as we have missed import line for css , scripts and toast.
import { loadScript,loadStyle } from "lightning/platformResourceLoader";
import { ShowToastEvent } from 'lightning/platformShowToastEvent'
Dhanik Lal Sahni is a Salesforce Solution Architect, Independent Consultant, and the founder of SalesforceCodex.com. With nearly two decades of IT experience and extensive expertise in Salesforce architecture, he helps startups and enterprises design scalable, secure, and high-performance CRM solutions using Sales Cloud, Service Cloud, Experience Cloud, Data Cloud, Apex, Lightning Web Components (LWC), and enterprise integration patterns.
Through SalesforceCodex, he shares practical tutorials, real-world implementation guides, enterprise architecture best practices, and interview preparation resources for Salesforce Developers, Architects, and Administrators.
Learn more about his Salesforce consulting and freelance services at dhaniksahni.com.
