SF-PD2 User Interface Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  import { showToast } from 'lightning/platformShowToastEvent';

  Why it's wrong here

  The lightning/platformShowToastEvent module does not export a function named showToast. The correct named export is ShowToastEvent, which is a class that extends Event. Attempting to import showToast will result in a build error because the export does not exist. Developers often confuse the method name with the class name, but the module only provides the ShowToastEvent class for manual instantiation and dispatch.

• ✗

  import ShowToastEvent from 'lightning/platformShowToastEvent';

  Why it's wrong here

  This uses a default import, but lightning/platformShowToastEvent does not have a default export. All exports from this module are named exports. Using a default import will cause a syntax or build error because the module does not provide a default export. The correct syntax requires curly braces around the named export ShowToastEvent. Developers must use named imports for all standard Lightning modules.

• ✓

  import { ShowToastEvent } from 'lightning/platformShowToastEvent';

  Why this is correct

  This import correctly brings the ShowToastEvent class from the lightning/platformShowToastEvent module. In LWC, the module name is 'lightning/platformShowToastEvent' and the named export is ShowToastEvent. Using this import, the developer can create a new ShowToastEvent with parameters like title, message, and variant, then dispatch it via this.dispatchEvent. This is the standard way to show toast notifications in Lightning Experience.

• ✗

  import { ShowToastEvent } from 'lightning/toastEvent';

  Why it's wrong here

  The module path 'lightning/toastEvent' does not exist in the Lightning Web Components framework. The correct module is 'lightning/platformShowToastEvent'. Using an incorrect module path will cause a module resolution error during compilation. Developers should always verify the exact module names from the official Salesforce documentation, as the framework provides a specific set of base Lightning components and modules with fixed names.