Salesforce Updated PDI Exam Questions and Answers by zarah

To pass data from a parent component to a child component, the developer can use either a custom event or a public property1. A custom event is a way for a component to communicate with its parent or ancestor components by sending a message that contains data. The parent component can listen for the event and handle it accordingly. A public property is a way for a parent component to pass data to a child component by setting an attribute on the child component’s HTML tag. The child component can access the data through the property’s value.

The developer cannot use the Apex controller class or invoke a method in the child component to pass data from the parent component. The Apex controller class is used to communicate with the server and perform business logic, not to pass data between components. Invoking a method in the child component is a way for the parent component to call a function defined in the child component, not to pass data to it. References:

• Inter-Component Communication Patterns for Lightning Web Components | Salesforce Developers Blog
• Communicate with Events - Lightning Web Components Developer Guide - Salesforce Developers
• Pass Data to Child Components - Lightning Web Components Developer Guide - Salesforce Developers

The developer should implement either a Lightning component or a Visualforce page that performs the HTTP REST callout, and use a Lightning Action or a Visualforce quick action to expose the component on the Opportunity detail page. These methods allow the developer to create a user interface that can capture the user input and trigger the callout based on a user-initiated action. The Lightning component or the Visualforce page can use the Apex controller to invoke the HTTP callout using the built-in HTTP classes, such as HttpRequest, HttpResponse, and Http. The Lightning Action or the Visualforce quick action can be added to the page layout of the Opportunity object and configured to display the component in a modal dialog or a panel.

Creating a Process Builder or an after update trigger to perform the HTTP REST callout is not a suitable method for this business requirement, because these methods do not provide a user interface or a user-initiated action. The Process Builder or the trigger would execute the callout whenever the Opportunity is updated, regardless of the user input or intention. This could result in unnecessary or unwanted callouts, as well as hitting the governor limits for callouts.

References: Invoking HTTP Callouts, Configuring an HTTP Callout Action, Create HTTP Callout for Salesforce Flow, Invoking Callouts Using Apex, [Prepare for Your Salesforce Platform Developer I Credential]

 The issue is that the value of the account type field is not being displayed correctly on the Visualforce page. This can be resolved by adding a getter method for the actType attribute in the custom controller. A getter method is used to retrieve the value of a private variable, ensuring that it’s read-only and cannot be modified by external classes or pages, thus maintaining encapsulation and security. References: The need for getter methods and their usage can be referenced in Apex basics where encapsulation, getters, and setters are discussed: Apex Basics & Database