DropDownListComponent

23 Sep 202513 minutes to read

The DropDownList component contains a list of predefined values, from which the user can choose a single value.

<ejs-dropdownlist></ejs-dropdownlist>

Properties

allowFiltering boolean

When allowFiltering is set to true, show the filter bar (search box) of the component.
The filter action retrieves matched items through the filtering event based on
the characters typed in the search TextBox.
If no match is found, the value of the noRecordsTemplate property will be displayed.

For more details about the filtering refer to Filtering documentation.

Defaults to false

allowObjectBinding boolean

Defines whether the object binding is allowed or not in the component.

Defaults to false

allowResize boolean

Gets or sets a value that indicates whether the DropDownList popup can be resized.
When set to true, a resize handle appears in the bottom-right corner of the popup,
allowing the user to resize the width and height of the popup.

Defaults to false

cssClass string

Sets CSS classes to the root element of the component that allows customization of appearance.

Defaults to null

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 []

debounceDelay number

Specifies the delay time in milliseconds for filtering operations.

Defaults to 300

enablePersistence boolean

Enable or disable persisting component’s state between page reloads.
If enabled, following list of states will be persisted.

1. value

Defaults to false

enableRtl boolean

Enable or disable rendering component in right to left direction.

Defaults to false

enableVirtualization boolean

Defines whether to enable virtual scrolling in the component.

Defaults to false

enabled boolean

Specifies a value that indicates whether the component is enabled or not.

Defaults to true

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}

filterBarPlaceholder string

Accepts the value to be displayed as a watermark text on the filter bar.

Defaults to 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’

floatLabelType FloatLabelType

Specifies whether to display the floating label above the input element.
Possible values are:

• Never: The label will never float in the input when the placeholder is available.
• Always: The floating label will always float above the input.
• Auto: The floating label will float above the input after focusing or entering a value in the input.

Defaults to Syncfusion.EJ2.Inputs.FloatLabelType.Never

footerTemplate any

Accepts the template design and assigns it to the footer container of the popup list.

For more details about the available template options refer to Template documentation.

Defaults to null

groupTemplate any

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

Defaults to null

headerTemplate any

Accepts the template design and assigns it to the header container of the popup list.

For more details about the available template options refer to Template documentation.

Defaults to null

htmlAttributes { : }

Allows additional HTML attributes such as title, name, etc., and
accepts n number of attributes in a key-value pair format.

 <ejs-dropdownlist [htmlAttributes]="htmlAttributes" [fields]="fields" [dataSource]="dataSource"></ejs-dropdownlist>

import { Component, ViewEncapsulation } from '@angular/core';

@Component({
  selector: 'app-root',
  styleUrls: ['app.component.css'],
  templateUrl: 'app.component.html',
  encapsulation: ViewEncapsulation.None
})
export class AppComponent {
  constructor() {}
  public htmlAttributes = { name: "country", placeholder: "Select a country", title: "DropDownList" };
  public fields = { text: 'Name' };
  public dataSource: { [key: string]: Object; }[] = [
  { Name: "Australia", Code: "AU" },
  { Name: "Bermuda", Code: "BM" },
  { Name: "Canada", Code: "CA" },
  { Name: "Cameroon", Code: "CM" },
  { Name: "Denmark", Code: "DK" }
];
}

Defaults to {}

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

index number|null

Gets or sets the index of the selected item in the component.

Defaults to null

isDeviceFullScreen boolean

Defines whether the popup opens in fullscreen mode on mobile devices when filtering is enabled. When set to false, the popup will display similarly on both mobile and desktop devices.

Defaults to true

itemTemplate any

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’

placeholder string

Specifies a short hint that describes the expected value of the DropDownList component.

Defaults to null

popupHeight string|number

Specifies the height of the popup list.

For more details about the popup configuration refer to
Popup Configuration documentation.

Defaults to ‘300px’

popupWidth string|number

Specifies the width of the popup list. By default, the popup width sets based on the width of
the component.

For more details about the popup configuration refer to
Popup Configuration documentation.

Defaults to ‘100%’

query Query

Accepts the external Query
that execute along with data processing.

 <ejs-dropdownlist [query]="query" [placeholder]="placeholder" [fields]="fields" [dataSource]="dataSource"></ejs-dropdownlist>

import { Component, ViewEncapsulation } from '@angular/core';
import { Query, DataManager, WebApiAdaptor } from '@syncfusion/ej2-data';

@Component({
  selector: 'app-root',
  styleUrls: ['app.component.css'],
  templateUrl: 'app.component.html',
  encapsulation: ViewEncapsulation.None
})
export class AppComponent {
  constructor() {}
  public query = new Query().select(['FirstName', 'EmployeeID']).take(10).requiresCount();
  public placeholder = "Select a name";
  public fields = { text: 'FirstName', value: 'EmployeeID' };
  public dataSource: new DataManager({
    url: 'https://ej2services.syncfusion.com/production/web-services/api/Employees',
    adaptor: new WebApiAdaptor,
    crossDomain: true
  });
}

Defaults to null

readonly boolean

When set to true, the user interactions on the component are disabled.

Defaults to false

showClearButton boolean

Specifies whether to show or hide the clear button.
When the clear button is clicked, value, text, and index properties are reset to null.

Defaults to false

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

text string|null

Gets or sets the display text of the selected item in the component.

Defaults to null

value number|string|boolean|object|null

Gets or sets the value of the selected item in the component.

Defaults to null

valueTemplate any

Accepts the template design and assigns it to the selected list item in the input element of the component.
For more details about the available template options refer to
Template documentation.
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

width string|number

Specifies the width of the component. By default, the component width sets based on the width of
its parent container. You can also set the width in pixel values.

Defaults to ‘100%’

zIndex number

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

Defaults to 1000

Methods

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

clear

Allows you to clear the selected values from the component.

Returns void

destroy

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

Returns void

disableItem

Method to disable specific item in the popup.

Parameter	Type	Description
item	string | number | object | HTMLLIElement	Specifies the item to be disabled.

Returns void

filter

To filter the data from given data source by using query

| Parameter | Type | Description |
|——|——|————-|
| dataSource | ` { : }[] | DataManager | string[] | number[] | boolean[] | Set the data source to filter. | | query (*optional*) | Query | Specify the query to filter the data. | | fields (*optional*) | [FieldSettingsModel`](./fieldSettingsModel) | Specify the fields to map the column in the data table. |

Returns void

focusIn

Sets the focus on the component for interaction.

Returns void

focusOut

Moves the focus from the component if the component is already focused.

Returns void

getDataByValue

Gets the data Object that matches the given value.

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

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

getItems

Gets all the list items bound on this component.

Returns Element[]

hidePopup

Hides the popup if it is in an open state.

Returns void

hideSpinner

Hides the spinner loader.

Returns void

showPopup

Opens the popup that displays the list of items.

Returns void

showSpinner

Shows the spinner loader.

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.

beforeOpen EmitType<Object>

Triggers when the popup before opens.

blur EmitType<Object>

Triggers when focus moves out from the component.

change EmitType<ChangeEventArgs>

Triggers when an item in a popup is selected or when the model value is changed by user.
Use change event to
Configure the Cascading DropDownList

close EmitType<PopupEventArgs>

Triggers when the popup is closed.

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.

filtering EmitType<FilteringEventArgs>

Triggers on typing a character in the filter bar when the
allowFiltering
is enabled.

For more details about the filtering refer to Filtering documentation.

focus EmitType<Object>

Triggers when the component is focused.

open EmitType<PopupEventArgs>

Triggers when the popup opens.

resizeStart EmitType<Object>

Triggers when the user starts resizing the DropDown popup.

resizeStop EmitType<Object>

Triggers when the user finishes resizing the DropDown popup.

resizing EmitType<Object>

Triggers continuously while the DropDown popup is being resized by the user.
This event provides live updates on the width and height of the popup.

select EmitType<SelectEventArgs>

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