AD0-E720 Adobe Commerce Front-End Developer Expert Questions and Answers

To access a view model within an existing block, the developer can use either of the following ways:

$block- > getData(‘view_model’): This method will return the view model object that is assigned to the argument name “view_model” in the layout XML file. For example:

< referenceBlock name=“blog_posts_list” > < arguments > < argument name=“view_model” xsi:type=“object” > ExampleObjectModel/ExampleObjectModel < /argument > < /arguments > < /referenceBlock >

In the template file, the developer can access the view model object by using:

$block- > getData(‘view_model’)

$block- > getData(‘viewModel’): This method will return the view model object that is assigned to the argument name “viewModel” in the layout XML file. For example:

< referenceBlock name=“blog_posts_list” > < arguments > < argument name=“viewModel” xsi:type=“object” > ExampleObjectModel/ExampleObjectModel < /argument > < /arguments > < /referenceBlock >

In the template file, the developer can access the view model object by using:

$block- > getData(‘viewModel’)

The following methods are not valid and will not work:

$block- > viewModel(): This method does not exist and will cause an error.

$block- > getViewHodel(): This method is misspelled and will cause an error.

To modify the width and height of all product images inside a theme, the developer needs to edit the view.xml file inside the etc directory of the theme. The view.xml file contains the configuration for the theme’s images, fonts, and layout. The images.xml file does not exist by default and is not used for configuring images. The theme.xml file is used for specifying the parent theme and other metadata of the theme. References: [view.xml], [theme.xml]

Template hints are a useful tool for frontend developers to determine which template is rendering a specific element on the storefront. Template hints can be turned on using either of these two methods:

In the Admin Panel, navigate to Stores > Configuration > Advanced > Developer > Debug. Set Enabled Template Path Hints for Storefront to Yes

On the command line, run the command; php bin/magento dev:template-hints:enable The other two options are incorrect because they do not exist as valid methods to turn on template hints. References:  Adobe Commerce Developer Documentation ,  Adobe Inc.

To delete a manually installed theme, the developer needs to remove the theme directory from the app/design/frontend directory and also delete the corresponding record from the theme table in the database. The theme:uninstall CLI command is only used for deleting themes that are installed as Composer packages. Disabling the theme from the backend admin configuration does not delete the theme files or records, but only makes it unavailable for use. References: [Delete a theme], [theme:uninstall]

Option A and Option C are both valid ways to apply a Knockout binding to show content under certain conditions. Option A uses the visible binding, which sets the display style of the element to none if the value is false. Option C uses the if binding, which removes or inserts the element from the DOM based on the value. Option B and Option D are incorrect because they use invalid syntax for Knockout bindings. Option B uses a colon instead of an equal sign to assign the value, and Option D uses a single quote instead of a double quote to enclose the value.

https://knockoutjs.com/documentation/binding-syntax.html

https://knockoutjs.com/documentation/binding-context.html

To completely overwrite _module.less of Orange_Checkout module in a custom theme, the developer should place the file in the Custom/theme/Orange_Checkout/web/css/source directory. This will override the default _module.less file from the Orange_Checkout module and apply the custom styles to the theme. The Custom/theme/Orange_Checkout/frontend/web/css/_module.less and Custom/theme/web/css/source/Orange_Checkout/_module.less paths are not valid and will not work, as they do not follow the theme structure or the module naming convention. References: [Theme structure], [Module naming convention]

To place a template file for a custom module, the developer should follow this path pattern:

app/code/ < Vendor > / < Module > /view/ < Area > /templates/ < Template >

In this case, the vendor name is Orange, the module name is Customer, the area is frontend, and the template name is customer-info.phtml. Therefore, the correct path is:

app/code/Orange/Customer/view/frontend/templates/customer-info.phtml

The following paths are not correct and will not work:

app/code/Orange/customer/view/frontend/web/templates/customer-info.phtml: This path is incorrect because it uses web instead of templates, which is used for storing web assets like CSS, JS, and images, not template files.

app/code/Orange/Customer/frontend/templates/customer-info.phtml: This path is incorrect because it misses the view directory, which is required for separating frontend and backend templates.

The favicon can be added to the < your_theme_dir > /Magento_Theme/web/ directory of a custom theme. The favicon should have the name favicon.ico and replace the default one from the Magento_Theme module. The < your_theme_dir > /web/ directory is used for storing web assets that are not specific to any module. The < your_theme_dir > /assets/images directory does not exist by default and is not used for storing favicons. References: [Add a favicon], [Theme structure]

To apply a knockout binding to a < div > to run a function, onClick(), when it’s clicked, the developer can use either of the following solutions:

A. < div data-bind=“click: onClick()” > < /div > : This solution will use the click binding to execute the onClick() function as an expression when the < div > is clicked. The function will be called with the current binding context as the first parameter and the event object as the second parameter.

C. < div data-bind=“click: onClick” > < /div > : This solution will use the click binding to execute the onClick function as a reference when the < div > is clicked. The function will be called with the current binding context as the first parameter and the event object as the second parameter.

The following solutions are not valid and will not work:

B. < div > < !-- ko click: ‘onClick’ -- > < !-- /ko -- > < /div > : This solution will use the virtual element syntax to apply the click binding, but it will pass a string literal instead of a function expression or reference. This will cause an error, as the click binding expects a function value.

D. < div click=“onClick” > < /div > : This solution will use a custom attribute instead of a data-bind attribute to apply the click binding. This is not supported by knockout and will not have any effect.

To override the core Magento UI library dropdowns in a custom theme, the developer needs to create a file named _dropdowns.less in the /web/css/source directory of the theme. This file will override the default _dropdowns.less file from the lib/web/css/source/lib directory and apply the custom styles to the dropdown elements. The lib/web/css/source/_dropdowns.less and /web/css/source/lib/_dropdowns.less files are not valid and will not work, as they do not follow the theme structure or the naming convention. References: [Dropdowns], [Theme structure]

In client-side compilation mode, the stylesheet customizations will display immediately after reloading a page in a browser. This is because in this mode, the LESS files are compiled into CSS files by the browser using JavaScript. This mode is useful for development and debugging purposes, as it allows quick changes and previews of the styles. However, this mode is not recommended for production, as it can affect the performance and compatibility of the site. The other modes, server-side compilation and LESS compilation, require running commands or tools to compile the LESS files into CSS files on the server side, which can take some time and delay the display of the customizations. References: [Compilation modes], [Compile LESS]

To alias URLs and third party libraries inside a requirejs-config.js file, the developer should use the paths configuration option. This option allows the developer to map module names to URLs or paths relative to the baseUrl. For example:

var config = { paths: { ‘jquery’: ‘https://code.jquery.com/jquery-3.6.0.min’, ‘custom’: ‘Vendor_Module/js/custom’ } };

This will map the module name ‘jquery’ to the URL of the jQuery library and the module name ‘custom’ to the path of the custom module. The developer can then use these module names in other modules or files without specifying the full URL or path.

Option A is not correct because it uses the shim configuration option, which is used to define dependencies and exports for non-AMD modules, not to alias URLs or paths. Option C is not correct because it uses the map configuration option, which is used to map module names to other module names for specific contexts, not to alias URLs or paths. References: [RequireJS configuration], [RequireJS paths]