DropDownBase

23 Sep 20257 minutes to read

DropDownBase component will generate the list items based on given data and act as base class to drop-down related components

Properties

actionFailureTemplate string|Function

Accepts the template and assigns it to the popup list content of the component
when the data fetch request from the remote server fails.

Defaults to ‘Request failed’

dataSource { : }[]|DataManager|string[]|number[]|boolean[]

Accepts the list items either through local or remote service and binds it to the component.
It can be an array of JSON Objects or an instance of
DataManager.

Defaults to []

enablePersistence boolean

Enable or disable persisting component’s state between page reloads.

Defaults to false

enableRtl boolean

Enable or disable rendering component in right to left direction.

Defaults to false

fields FieldSettingsModel

The fields property maps the columns of the data table and binds the data to the component.

text - Maps the text column from data table for each list item.
value - Maps the value column from data table for each list item.
iconCss - Maps the icon class column from data table for each list item.

groupBy - Group the list items with it’s related items by mapping groupBy field.

<input type="text" tabindex="1" id="list"> </input>

let customers: DropDownList = new DropDownList({
   dataSource:new DataManager({ url:'http://js.syncfusion.com/demos/ejServices/Wcf/Northwind.svc/' }),
   query: new Query().from('Customers').select(['ContactName', 'CustomerID']).take(5),
   fields: { text: 'ContactName', value: 'CustomerID' },
   placeholder: 'Select a customer'
});
customers.appendTo("#list");

Defaults to {text: null, value: null, iconCss: null, groupBy: null, disabled: null}

filterType FilterType

Determines on which filter type, the component needs to be considered on search action.
The FilterType and its supported data types are

FilterType	Description	Supported Types
StartsWith	Checks whether a value begins with the specified value.	String
EndsWith	Checks whether a value ends with specified value.	String
Contains	Checks whether a value contains with specified value.	String

The default value set to StartsWith, all the suggestion items which contain typed characters to listed in the suggestion popup.

Defaults to ‘StartsWith’

groupTemplate string|Function

Accepts the template design and assigns it to the group headers present in the popup list.

Defaults to null

ignoreAccent boolean

ignoreAccent set to true, then ignores the diacritic characters or accents when filtering.

ignoreCase boolean

When set to ‘false’, consider the case-sensitive on performing the search to find suggestions.
By default consider the casing.

Defaults to true

itemTemplate string|Function

Accepts the template design and assigns it to each list item present in the popup.
We have built-in template engine
which provides options to compile template string into a executable function.
For EX: We have expression evolution as like ES6 expression string literals.

Defaults to null

locale string

Overrides the global culture and localization value for this component. Default global culture is ‘en-US’.

Defaults to ‘en-US’

noRecordsTemplate string|Function

Accepts the template design and assigns it to popup list of component
when no data is available on the component.

Defaults to ‘No records found’

query Query

Accepts the external Query
which will execute along with the data processing.

Defaults to null

sortOrder SortOrder

Specifies the sortOrder to sort the data source. The available type of sort orders are

None - The data source is not sorting.
Ascending - The data source is sorting with ascending order.
Descending - The data source is sorting with descending order.

Defaults to null

zIndex number

specifies the z-index value of the component popup element.

Defaults to 1000

Methods

addEventListener

Adds the handler to the given event listener.

Parameter	Type	Description
eventName	`string`	A String that specifies the name of the event
handler	`Function`	Specifies the call to run when the event occurs.

Returns void

addItem

Adds a new item to the popup list. By default, new item appends to the list as the last item,
but you can insert based on the index parameter.

Parameter	Type	Description
items	` `{ : }`[] `\|` `{ : }` `\|` string `\|` boolean `\|` number `\|` string[] `\|` boolean[] `\|` number[]`	Specifies an array of JSON data or a JSON data.
itemIndex (optional)	`number`	Specifies the index to place the newly added item in the popup list.

Returns void

appendTo

Appends the control within the given HTML element

Parameter	Type	Description
selector (optional)	`string` \| `HTMLElement`	Target element where control needs to be appended

Returns void

attachUnloadEvent

Adding unload event to persist data when enable persistence true

Returns void

dataBind

When invoked, applies the pending property changes immediately to the component.

Returns void

destroy

Removes the component from the DOM and detaches all its related event handlers. It also removes the attributes and classes.

Returns void

detachUnloadEvent

Removing unload event to persist data when enable persistence true

Returns void

getDataByValue

Gets the data Object that matches the given value.

Parameter	Type	Description
value	`string` \| `number` \| `boolean` \| `object`	Specifies the value of the list item.

Returns * { : }** | *string | number | boolean

getItems

Gets all the list items bound on this component.

Returns Element[]

getLocalData

Returns the persistence data for component

Returns any

getRootElement

Returns the route element of the component

Returns HTMLElement

handleUnload

Handling unload event to persist data when enable persistence true

Returns void

refresh

Applies all the pending property changes and render the component again.

Returns void

removeEventListener

Removes the handler from the given event listener.

Parameter	Type	Description
eventName	`string`	A String that specifies the name of the event to remove
handler	`Function`	Specifies the function to remove

Returns void

Inject

Dynamically injects the required modules to the component.

Parameter	Type	Description
moduleList	`Function[]`	?

Returns void

Events

actionBegin EmitType<Object>

Triggers before fetching data from the remote server.

actionComplete EmitType<Object>

Triggers after data is fetched successfully from the remote server.

actionFailure EmitType<Object>

Triggers when the data fetch request from the remote server fails.

created EmitType<Object>

Triggers when the component is created.

dataBound EmitType<Object>

Triggers when data source is populated in the popup list..

destroyed EmitType<Object>

Triggers when the component is destroyed.

select EmitType<SelectEventArgs>

Triggers when an item in the popup is selected by the user either with mouse/tap or with keyboard navigation.