Developers Changed PDI Questions

Aura Components and Lightning Web Components are two technologies that are built on a framework that fully supports the business requirement of building a responsive application capable of responding to touch events, that will be executed on stateful clients. Both technologies are part of the Lightning Component Framework, which is a modern UI framework for developing dynamic web apps for mobile and desktop devices. The Lightning Component Framework uses standard web technologies, such as HTML, CSS, JavaScript, and Web Components, to create reusable and interoperable components that can adapt to different screen sizes, devices, and orientations. The framework also provides features such as data binding, event handling, state management, and server-side integration, to enable developers to create rich and interactive user interfaces.

Aura Components are the original technology for creating Lightning components. They use a custom XML-based markup language, Aura, to define the component structure and behavior. Aura Components can respond to touch events using the ui:input component, which provides a generic input element that can handle different input types, such as text, number, date, checkbox, radio, toggle, and email. The ui:input component also supports touch gestures, such as swipe, tap, and pinch, by using the ontouchstart, ontouchend, ontouchmove, and ontouchcancel attributes. Aura Components are stateful, meaning that they maintain their state on the client-side and communicate with the server only when necessary. This reduces the network traffic and improves the performance and user experience.

Lightning Web Components are the newer technology for creating Lightning components. They use standard HTML, CSS, and JavaScript to define the component structure and behavior. Lightning Web Components can respond to touch events using the standard HTML input element, which provides a native input element that can handle different input types, such as text, number, date, checkbox, radio, toggle, and email. The input element also supports touch gestures, such as swipe, tap, and pinch, by using the standard touch event listeners, such as touchstart, touchend, touchmove, and touchcancel. Lightning Web Components are also stateful, meaning that they maintain their state on the client-side and communicate with the server only when necessary. This reduces the network traffic and improves the performance and user experience.

Visualforce Components and Visualforce Pages are two technologies that are not built on a framework that fully supports the business requirement of building a responsive application capable of responding to touch events, that will be executed on stateful clients. Visualforce Components are reusable UI elements that can be used in Visualforce Pages. Visualforce Pages are web pages that can display and interact with Salesforce data and logic. Visualforce Components and Pages use a custom XML-based markup language, Visualforce, to define the UI elements and behavior. Visualforce Components and Pages can be made responsive by using the Salesforce Lightning Design System (SLDS), which is a collection of design guidelines, components, and resources that enable developers to create consistent and beautiful user interfaces across devices. However, Visualforce Components and Pages do not have native support for touch events, and require custom JavaScript code to handle them. Visualforce Components and Pages are also stateless, meaning that they do not maintain their state on the client-side and communicate with the server on every request. This increases the network traffic and affects the performance and user experience.

References:

• Lightning Component Framework
• Aura Components Developer Guide
• Lightning Web Components Developer Guide
• Visualforce Developer Guide
• Salesforce Lightning Design System

The developer should implement a callout from a queueable class called from a trigger to accomplish this. A callout is a request that is sent from Salesforce to an external service, such as a REST endpoint in the ERP system1. A queueable class is an Apex class that implements the Queueable interface and can be executed asynchronously by adding it to the Apex job queue2. A trigger is an Apex script that executes before or after specific data manipulation language (DML) events on a Salesforce object, such as insert, update, or delete3.

The reason why this option is the best is because:

• A callout from a future method called from a trigger (option A) is not recommended, because future methods have some limitations, such as not being able to pass sObjects as parameters, not being able to chain future calls, and not being able to monitor the status of the execution4.
• A callout from a schedulable class called from a scheduled job (option B) is not suitable, because scheduled jobs run at a specified time or interval, and not in response to a data change event, such as setting the order status to "Placed"5.
• A flow with a callout from an invocable method (option C) is not feasible, because flows cannot be triggered by data changes, but only by user actions, such as clicking a button, or by process automation tools, such as Process Builder or Workflow.

References:

• 1: Callouts | Apex Developer Guide | Salesforce Developers
• 2: Queueable Apex | Apex Developer Guide | Salesforce Developers
• 3: Triggers | Apex Developer Guide | Salesforce Developers
• 4: Using the Future Annotation | Apex Developer Guide | Salesforce Developers
• 5: Schedulable Interface | Apex Developer Guide | Salesforce Developers
• : [Flow Trigger Workflow Actions | Salesforce Help]

The Aura application event propagation framework supports three phases for the propagation of application events: capture, bubble, and default. The capture and bubble phases are similar to DOM handling patterns and provide an opportunity for interested components to interact with an event and potentially control the behavior for subsequent handlers. The default phase preserves the framework’s original handling behavior and can be useful for handling application events that affect components in different sub-trees of your app. The emit and control phases are not part of the Aura application event propagation framework. References: Application Event Propagation, Application Events, Communicate with Events

Unit tests are methods that verify whether a particular piece of code is working properly. Unit tests can be run synchronously or asynchronously, and can be used to test Apex classes, triggers, and Visualforce controllers. Unit tests can also use system methods to set or override certain system properties, such as the current user, the current time, or the created date of a record. These methods are useful for testing different scenarios or behaviors that depend on these properties. For example, a unit test can use the System.runAs() method to execute a block of code as a different user, or the System.Test.setCreatedDate() method to set the created date of an sObject to a past or future date. See Testing Apex1 for more details. References: 1: Testing Apex | Apex Developer Guide | Salesforce Developers(https://stackoverflow.com/questions/767567/what-to-test-in-unit-testing-a-method-or-a-scenario)