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Tree Dropdown

<et2-tree-dropdown> | Et2TreeDropdown
Since 23.1

A tree that is hidden in a dropdown

Slots

Name Description
label The input’s label. Alternatively, you can use the label attribute.
prefix Used to prepend a presentational icon or similar element to the combobox.
suffix Used to append a presentational icon or similar element to the input.
expand-icon The icon to show when the control is expanded and collapsed. Rotates on open and close.
help-text Text that describes how to use the input. Alternatively, you can use the help-text attribute.

Learn more about using slots.

Properties

Name Description Reflects Type Default
accesskey Accesskey provides a hint for generating a keyboard shortcut for the current element. The attribute value must consist of a single printable character. string -
actions Actions (passed to the tree) {} {}
align Used by Et2Box to determine alignment. Allowed values are left, right string -
autofocus Have browser focus this input on load. Overrides etemplate2.focusOnFirstInput(), use only once per page https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input#attributes boolean -
class CSS Class. This class is applied to the outside, on the web component itself. Due to how WebComponents work, this might not change anything inside the component. string -
data Set the dataset from a CSV string -
deferredProperties
Any attribute that refers to row content cannot be resolved immediately, but some like booleans cannot stay a string because it’s a boolean attribute. We store them for later, and parse when they’re fully in their row. If you are creating a widget that can go in a nextmatch row, and it has boolean attributes that can change for each row, add those attributes into deferredProperties - -
disabled Defines whether this widget is visibly disabled. The widget is still visible, but clearly cannot be interacted with. Widgets disabled in the template will not return a value to the application code, even if re-enabled via javascript before submitting. To allow a disabled widget to be re-enabled and return a value, disable via javascript in the app’s et2_ready() instead of an attribute in the template file. boolean false
dom_id
Get the actual DOM ID, which has been prefixed to make sure it’s unique. string -
emptyLabel Textual label for first row, eg: ‘All’ or ‘None’. It’s value will be ″ String ""
hasFeedbackFor
Get a list of feedback types string[] -
helpText
help-text
The component’s help text. If you need to display HTML, use the help-text slot instead. string ""
hidden The widget is not visible. As far as the user is concerned, the widget does not exist. Widgets hidden with an attribute in the template may not be created in the DOM, and will not return a value. Widgets can be hidden after creation, and they may return a value if hidden this way. boolean -
id
Get the ID of the widget string -
label The label of the widget Legacy support for labels with %s that get wrapped around the widget Not the best way go with webComponents - shouldn’t modify their DOM like this string -
noLang Disable any translations for the widget boolean -
open Indicates whether the dropdown is open. You can toggle this attribute to show and hide the tree, or you can use the show() and hide() methods and this attribute will reflect the open state. boolean false
parentId Parent is different than what is specified in the template / hierarchy. Widget ID of another node to insert this node into instead of the normal location string -
placeholder Placeholder text to show as a hint when the select is empty. string ""
select_options Select box options Will be found automatically based on ID and type, or can be set explicitly in the template using SelectOption[] -
statustext Tooltip which is shown for this element on hover string -
styles
WebComponent * - -
tagTag
Tag used for rendering tags when multiple=true Used for creating, finding & filtering options. StaticValue -
translate
List of properties that get translated Done separately to not interfere with properties - if we re-define label property, labels go missing. - -
value Selected tree leaves string | string[] -
_optionRenderPromise
When we create the select option elements, it takes a while. If we don’t wait for them, it causes issues in SlSelect Promise -
_optionTargetNode
Get the node where we’re putting the options If this were a normal selectbox, this would be just the HTMLElement -
needed
Compatibility for deprecated name “needed”
use required instead
- -
options
Get property-values as object
use widget methods
object -
readOnly
Lion mapping
true
- -
supportedWidgetClasses
et2_widget compatability
Legacy compatability. Some legacy widgets check their parent to see whats allowed
array []
updateComplete A read-only promise that resolves when the component has finished updating.

Learn more about attributes and properties.

Events

Name React Event Description Event Detail
change Emitted when the control’s value changes. Event
sl-show Emitted when the suggestion menu opens. -
sl-after-show Emitted after the suggestion menu opens and all animations are complete. -
sl-hide Emitted when the suggestion menu closes. -
sl-after-hide Emitted after the suggestion menu closes and all animations are complete. -

Learn more about events.

Methods

Name Description Arguments
blur() Removes focus from the control. -
checkCreateNamespace() Checks whether a namespace exists for this element in the content array. If yes, an own perspective of the content array is created. If not, the parent content manager is used. Constructor attributes are passed in case a child needs to make decisions -
clone() Creates a copy of this widget. _parent: et2_widget
createElementFromNode() Create a et2_widget from an XML node. First the type and attributes are read from the node. Then the readonly & modifications arrays are checked for changes specific to the loaded data. Then the appropriate constructor is called. After the constructor returns, the widget has a chance to further initialize itself from the XML node when the widget’s loadFromXML() method is called with the node. _node: , _name:
et2HandleBlur() If the value is unchanged, put any held validation messages back Named et2HandleBlur to avoid overwriting handleBlur() in Shoelace components _ev: FocusEvent
et2HandleFocus() When input receives focus, clear any validation errors. If the value is the same on blur, we’ll put them back The ones from the server (ManualMessage) can interfere with submitting. Named et2HandleFocus to avoid overwriting handleFocus() in Shoelace components _ev: FocusEvent
focus() Sets focus on the control. options: FocusOptions
getArrayMgr() Returns the array manager object for the given part managed_array_type: string
getArrayMgrs() Returns an associative array containing the top-most array managers. _mgrs: object
getChildren() Get child widgets Use .children to get web component children -
getInputNode() Get input to e.g. set aria-attributes -
getInstanceManager() Returns the instance manager -
getPath() Returns the path into the data array. By default, array manager takes care of this, but some extensions need to override this -
getRoot() Returns the base widget Usually this is the same as getInstanceManager().widgetContainer -
handleComboboxKeyDown() Keyboard events that the search input did not grab (tags, otion navigation) event: KeyboardEvent
hide() Hides the tree. -
iconTemplate() Get the icon for the select option option:
isValid() Used by etemplate2 to determine if we can submit or not messages:
loadFromXML() Load extra stuff from the template node. In particular, we’re looking for any _node: Element
loadingFinished() Needed for legacy compatability. promises: Promise[]
localSearch() If you have a local list of options, you can search through them on the client and include them in the results. This is done independently from the server-side search, and the results are merged. search: string, searchOptions: object, localOptions: DataType[], options: object
optionSearch() Search options for a given value, returning the first matching option value: string, options: SelectOption[], searchKey: string, childKey: string
parseXMLAttrs() The parseXMLAttrs function takes an XML DOM attributes object and adds the given attributes to the _target associative array. This function also parses the legacyOptions. N.B. This is only used for legacy widgets. WebComponents use transformAttributes() and do their own handling of attributes. _attrsObj: , _target: object, _proto: et2_widget
set_label() NOT the setter, since we cannot add to the DOM before connectedCallback() TODO: This is not best practice. Should just set property, DOM modification should be done in render https://lit-element.polymer-project.org/guide/templates#design-a-performant-template value: string
setArrayMgr() Sets the array manager for the given part _part: string, _mgr: object
setArrayMgrs() Sets all array manager objects - this function can be used to set the root array managers of the container object. _mgrs: object
setInstanceManager() Set the instance manager Normally this is not needed as it’s set on the top-level container, and we just return that reference manager: etemplate2
show() Shows the tree. -
submit() Called whenever the template gets submitted. We return false if the widget is not valid, which cancels the submission. _values:
updated() A property has changed, and we want to make adjustments to other things based on that changedProperties: PropertyValues
validate() Massively simplified validate, as compared to what ValidatorMixin gives us, since ValidatorMixin extends FormControlMixin which breaks SlSelect’s render() We take all validators for the widget, and if there’s a value (or field is required) we check the value with each validator. For array values we check each element with each validator. If the value does not pass the validator, we collect the message and display feedback to the user. We handle validation errors from the server with ManualMessages, which always “fail”. If the value is empty, we only validate if the field is required. skipManual:
_emptyLabelTemplate() Render the “empty label”, used when the selectbox does not currently have a value -
_handleClick() Click handler calling custom handler set via onclick attribute to this.onclick _ev: MouseEvent
_labelTemplate() Common sub-template to add a label. This goes inside the form control wrapper div, before and at the same depth as the input controls. -
_oldChange() Change handler calling custom handler set via onchange attribute _ev: Event
_optionTemplate() Render a single option Override this method to specify how to render each option. In a normal selectbox, this would be something like: <option value="${option.value}" title="${option.title}" ?selected=${option.value == this.modelValue}> ${option.label} </option>`; but you can do whatever you need. To use a different WebComponent, just use its tag instead of “option”. We should even be able to pass the whole SelectOption across <special-option .value=${option}></special-option> option: SelectOption
_set_label() Do some fancy stuff on the label, splitting it up if there’s a %s in it Normally called from updated(), the “normal” setter stuff has already been run before this is called. We only override our special cases (%s) because the normal label has been set by the parent value: string
_setAriaAttributes() Set aria-attributes on our input node -
destroy() et2_widget compatability
true
-
set_class() Set the widget class
Use this.class or this.classList instead
new_class: string
set_disabled() Wrapper on this.disabled because legacy had it.
Use widget.disabled for visually disabled, widget.hidden for visually hidden. Widgets that are hidden from the server via attribute or $readonlys will not be created. Widgets that are disabled from the server will not return a value to the application code.
value: boolean
set_select_options() Set select options
assign to select_options
new_options: SelectOption[] | { [key : string] : string }[]
set_statustext() supports legacy set_statustext
use this.statustext
value: string

Learn more about methods.

Parts

Name Description
form-control The form control that wraps the label, input, and help text.

Learn more about customizing CSS parts.