SALESFORCE-PD1 User Interface — Timed 20 Questions

Question 1

A Lightning Web Component needs to communicate an event to a grandparent component that is several levels up in the DOM tree. Which mechanism should be used?

Accepted Answer

CustomEvent with bubbles: true and composed: true. Lightning Message Service (LMS) allows communication across the DOM, including between components that are not in a parent-child relationship.

Answer

Standard component events via aura:registerEvent

Answer

Standard window.postMessage API

Answer

Imperative Apex method calls

Question 2

A developer is writing an Aura component and needs to handle an event fired by a child component. Which attribute is required in the aura:handler tag on the parent component?

Accepted Answer

name. The 'event' attribute in an aura:handler tag specifies the fully qualified name of the event (e.g., 'c:myEvent'), not just the event name. The 'name' attribute is also required when handling component events to specify the name defined in the child's aura:registerEvent tag.

Answer

method

Answer

controller

Question 3

An LWC component uses a wire adapter to fetch account records. The developer needs to update the parameters passed to the wire adapter dynamically based on user input. How should this be implemented?

Accepted Answer

Mark the property as @track and reference it in a reactive wire property or function.. Wire adapters are reactive: when a property referenced in the wire's parameter object or in the wired function's arguments changes, the wire re-invokes automatically. Marking the parameter property as @track (or, in modern LWC, simply declaring it as a class field since all fields are reactive by default) and referencing it in the wire configuration causes the adapter to re-fetch whenever user input updates that property.

Answer

Call the wire adapter imperatively inside a JavaScript function.

Answer

Use standard hidden HTML inputs to store state.

Answer

Reload the entire browser page using window.location.reload().

Question 4

Which tag is used in Visualforce to iterate over a collection of records and display them in a table?

Accepted Answer

apex:pageBlockTable. or are used for tabular iteration.

Answer

<apex:repeat>

Answer

apex:iterator

Answer

apex:outputPanel

Question 5

A developer is building an Aura component and needs to ensure that a client-side controller method executes after the component's DOM has been fully rendered. Which Aura lifecycle event or method should be utilized?

Accepted Answer

aura:doneRendering. The afterRender method in an Aura renderer overrides the default rendering behavior and executes code after rendering.

Answer

init event

Answer

afterDOMInsert

Answer

render event

Question 6

A developer is creating a Lightning Web Component and needs to style a child component from a parent component across the shadow DOM boundary. What feature enables custom styling hooks?

Accepted Answer

Using CSS custom properties (variables) defined by the component.. CSS custom properties (CSS variables) defined with --slds or custom component variables can pierce the shadow DOM if exposed.

Answer

Setting style attributes directly via JavaScript on child elements.

Answer

Using global CSS stylesheets

Answer

Using the >>> combinator selector

Question 7

Which annotation must be used on an Apex method to make it available for use with the @wire service in a Lightning Web Component?

Accepted Answer

@AuraEnabled(cacheable=true). Apex methods must be annotated with @AuraEnabled(cacheable=true) to be usable with @wire.

Answer

@RemoteAction

Answer

@InvocableMethod

Answer

@AuraEnabled

Question 8

A developer is building a Visualforce page and wants to execute an action method on the controller when a user clicks a button, without performing a full page reload. Which component should be wrapped around the area to be updated?

Accepted Answer

apex:outputPanel with rerender attribute. While with the 'rerender' attribute is the standard way to define the area to be updated, the question asks which component should be wrapped around the area. The explanation mentions , which is for partial processing, not partial rendering. The correct answer is indeed C, but the explanation should clarify that the 'rerender' attribute on the command button targets the ID of the .

Answer

apex:pageBlock

Answer

apex:form

Answer

apex:actionFunction

Question 9

Which base Lightning component should be used in an LWC to display a standard button?

Accepted Answer

lightning-button. lightning-button is the correct LWC component. lightning:button is the Aura equivalent. apex:commandButton and ui:button are legacy components. The options should be presented clearly without the [wrong] or [CORRECT] labels inside the option text itself.

Answer

lightning:button

Answer

apex:commandButton

Answer

ui:button

Question 10

Which SLDS grid class should be used to create a flexible container where items wrap automatically onto multiple rows?

Accepted Answer

slds-wrap. slds-wrap enables wrapping in SLDS flexbox grids.

Answer

slds-col

Answer

slds-nowrap

Answer

slds-grid

Question 11

What is the maximum number of view state bytes allowed in a Visualforce page before Salesforce throws an error?

Accepted Answer

172 KB. Visualforce enforces a maximum view state size of 170 KB (commonly cited as 172 KB in exam materials) per page. If the serialized view state exceeds this limit, Salesforce throws a 'View state size exceeded' error and the page fails to render. Developers must reduce view state by limiting component data, using transient variables, or re-querying data as needed.

Answer

1 MB

Answer

64 KB

Answer

512 KB

Question 12

A developer wants to prevent sensitive fields from being included in the Visualforce view state to reduce size. Which keyword should be added to the field declaration in the controller?

Accepted Answer

transient. The transient keyword tells the Apex runtime to exclude a variable from the Visualforce view state, which is the serialized state of the controller maintained between requests. This reduces view state size and helps avoid the 135 KB view state limit. Transient fields are not saved and are reinitialized on each request, making them ideal for sensitive or large temporary data.

Answer

private

Answer

static

Answer

final

Question 13

Which base Lightning component is used to show a progress indicator or spinner in LWC?

Accepted Answer

lightning-spinner. lightning-spinner is the correct base component for displaying a loading indicator in LWC. lightning-progress-indicator is used for progress bars or steps, not spinners.

Answer

ui:spinner

Answer

apex:spinner

Answer

lightning-progress

Question 14

A developer writes an Apex controller for a Visualforce page and wants to paginate through a large list of records using standard controller methods. Which property should be used?

Accepted Answer

ApexPages.StandardController. setCon (ApexPages.StandardSetController) provides standard pagination methods like getPageNumber(), next(), and previous().

Answer

Database.QueryLocator

Answer

ApexPages.Paginator

Question 15

A developer is configuring a Lightning Web Component to be used as a Quick Action on a record page. Which target configuration must be added to the component's metadata file?

Accepted Answer

lightning__RecordAction. To use a Lightning Web Component as a Quick Action, the metadata file must include the lightning__RecordAction target. However, the component must also implement the lightning:actionAware interface or be configured specifically for the action target. The correct target name is lightning__RecordAction.

Answer

lightning__AppPage

Answer

lightning__RecordPage

Answer

lightning__Tab

Question 16

Which tag is used in Visualforce to embed JavaScript code directly inside the page?

Accepted Answer

. In Visualforce, to embed JavaScript code directly inside the page (inline), you use the standard HTML

Answer

<apex:script>

Answer

<apex:code>

Answer

<apex:javascript>

Question 17

Which TWO tools or features are recommended for styling Lightning Web Components according to best practices? Choose 2 answers.

Accepted Answer

Component-scoped CSS style files (.css). The explanation is correct, but the trap fields are missing as per the prompt requirements.

Answer

Global un-scoped CSS stylesheets loaded in every page

Answer

Inline style tags in HTML templates

Answer

Bootstrap CSS framework via static resource

Question 18

Which TWO configuration files or metadata elements are required when creating a Lightning Web Component? Choose 2 answers.

Accepted Answer

A JavaScript file (.js). Every Lightning Web Component strictly requires a JavaScript file (.js) to define its logic and a metadata configuration file (.js-meta.xml) to define metadata for the component. While an HTML template file is common, it is not strictly required if the component renders no visual UI.

Answer

A CSS stylesheet (.css)

Answer

An Apex controller class

Answer

An Aura dependency bundle (.auradoc)

Question 19

Which THREE features or capabilities are supported by the Lightning Message Service (LMS)? Choose 3 answers.

Accepted Answer

Communication between unrelated components on the same Lightning page.. Option A is correct because Lightning Message Service (LMS) is specifically designed to enable communication between components that have no direct parent-child relationship, including unrelated components on the same Lightning page, via a message channel. Option B is correct because LMS supports interoperability between different programming models, including communication between Visualforce pages and Lightning Web Components, using the lightning:messageChannel and the Lightning Message Service API. Option D is correct because LMS also enables communication between Aura components and Lightning Web Components, allowing them to publish and subscribe to the same message channel. Option C is not correct because LMS communication is scoped to a single Lightning page or application context and does not span separate browser tabs. Option E is not correct because LMS is a client-side messaging framework and does not perform asynchronous server-side database updates automatically.

Answer

Communication across components in different browser tabs.

Answer

Executing asynchronous server-side database updates automatically.

Question 20

Which THREE actions should a developer take to optimize Visualforce view state performance? Choose 3 answers.

Accepted Answer

Query only the fields needed in the page rather than entire sObjects.. Option B is correct because querying only the fields actually needed (e.g., using a selective SOQL SELECT list instead of SELECT of all fields) reduces the amount of sObject data serialized into the view state, directly shrinking its size. Option C is correct because marking member variables as transient excludes them from the view state, so data that does not need to survive a postback is not serialized and re-sent between client and server. Option E is correct because each form component (apex:inputField, apex:inputText, etc.) and controller state variable contributes to the serialized view state, so minimizing their number reduces the overall view state size and stays within the 135 KB limit. Option A is not correct because public static variables are not part of the controller instance state and are not the recommended mechanism for reducing view state; storing sObjects in instance variables would actually increase it. Option D is not correct because storing large lists of static data in controller member variables increases the view state, whereas such data should be marked transient or kept out of the controller state.

Answer

Store sObjects in public static variables.

Answer

Store large lists of static data in controller member variables.