UI Component Reference: List Box

A listbox can be linked to a domain class (via the domain tag or a Dependency arrow), to display data from the domain class’ relevant API endpoint. Each row shows a single attribute. The selected value is always the domain object’s id attribute, though UI listeners are given the whole domain object. A listbox can also be linked to an Enumeration, in which case it will display ‘hardwired’ enum values. The selected value is then the enum name.

Which wireframe component?

Depending which modeling tool you’re using, add the following component from the palette into the wireframe:

Tool	Wireframe component(s)
Enterprise Architect	List
Magic Draw	List

Capabilities

	Notes
Domain item chooser	The component can be used as an item selector, to choose a domain object. Can be used in a form, or simply to generate an ‘item chosen’ event.
Enum chooser	The component can be used to choose from an array of Enumeration values. Can be used in a form, or simply to generate an ‘item chosen’ event.
Multi selection	Multiple items can be chosen. To enable, add a tagged value `multi selection` with the value `true`.
Domain data	The component can be linked to a domain class, via the `domain` tag or a dependency arrow. The component will show data loaded from the domain class’ relevant API endpoint.
Bind target	Other components can listen and react to this component’s’ UI events, via their `bind` tag or a dependency arrow pointing to this component.

Filtering the list

If you want to filter the items that appear in the list, add a tagged value called filter. This can include a JavaScript/TypeScript predicate.

Three values are available to the predicate:

the domain item (one of the rows in the list); the name will be the domain class name as “lowerCamelCase”, e.g. video or videoReview
index - the position of this item in the (unfiltered) list, zero-indexed
an array of the whole list, named e.g. videoItems or videoReviewItems

The predicate must be a valid JavaScriptor TypeScript expression, and must resolve to boolean. If not, the whole React build might break, so tread carefully!

We recommend writing the predicate first in the generated React code and testing it, before copying it into the model.

Example predicates:

video.url.startsWith("https://")

video.name.length > 0

index % 2 === 1

Or to truncate the list to the first 20 items:

index < 20

The same filter tag is also available on other data-linked components - ComboBox, Table, Map.

Tagged values

Tag	Allowed values	Notes
`domain`		Links a component to a domain class, and optionally an attribute. Depending on the component, it will then use the domain data in some way, e.g. to populate a table or listbox with domain data for selection. The linked data will be loaded via the domain class’ matching REST API endpoint, with loading state managed in the UI via a Redux domain selector. Please note: This tag is the same as connecting the element to a domain class with a Dependency arrow.
`display domain`		Specifies which domain class attribute to display. For cases where the display attribute/relationship is different from the ‘data’ domain attribute/relationship.
`form domain`		For Domain Chooser UI Elements (listbox, ComboBox), where the form attribute/relationship is different from the ‘data’ domain attribute/relationship, as two domain classes are involved.
`filter`		Define a single-line predicate (valid TypeScript expression that evaluates to a boolean) to filter a UI list.
`css class`	Any CSS class name, without a preceding `.`	Adds the specified CSS class (or classes) to the UI element. If you define a class in a custom CSS file, you can apply it to a component using this tag. CodeBot will also recognise any ‘standard’ Bootstrap CSS classes such as `h1`, `h2` etc; their defined behaviour will be carried over to any future UI platforms that CodeBot generates.
`variant css class`
`cell css class`
`variant` or: `appearance`	Must be one of: primary, secondary, success, danger, warning, info, light, dark, link	Changes a UI Element’s appearance. The allowed values are based on Bootstrap’s variant CSS classes. For React Labels, this will turn the label into an “Alert” component, with a background and text colour matching the variant. Useful for callouts, notes and static warnings (“Clicking OK will delete all your data”).
`multi selection` or: `multiple selection`, `multi`	true or false DEFAULT: `false`	If `true`, multiple items can be selected; if ‘false’, it’s single-selection only.

Tagged values for all model elements including UI component types