React DropDownBox Methods

This section describes members used to manipulate data.

beginUpdate()

Prevents the UI component from refreshing until the endUpdate() method is called.

The beginUpdate() and endUpdate() methods prevent the UI component from excessive updates when you are changing multiple UI component settings at once. After the beginUpdate() method is called, the UI component does not update its UI until the endUpdate() method is called.

blur()

Removes focus from the input element.

jQuery

Call Methods

Angular

Call Methods

Vue

Call Methods

React

Call Methods

focus

close()

Closes the drop-down editor.

jQuery

Call Methods

Angular

Call Methods

Vue

Call Methods

React

Call Methods

content()

Gets the popup window's content.

Return Value:

HTMLElement | jQuery

An HTML element or a jQuery element when you use jQuery.

jQuery

Call Methods

Angular

Call Methods

Vue

Call Methods

React

Call Methods

defaultOptions(rule)

Specifies the device-dependent default configuration properties for this component.

Parameters:

rule:

Object

The component's default device properties.

Object structure:

Name	Type	Description
device	Device \| Function	Device parameters. When you specify a function, get information about the current device from the argument. Return true if the properties should be applied to the device.
options	Object	Options to be applied.

Name

Type

Description

device

Device

|

Function

Device parameters.
When you specify a function, get information about the current device from the argument. Return true if the properties should be applied to the device.

options

Object

Options to be applied.

defaultOptions is a static method that the UI component class supports. The following code demonstrates how to specify default properties for all instances of the DropDownBox UI component in an application executed on the desktop.

jQuery

JavaScript

DevExpress.ui.dxDropDownBox.defaultOptions({ 
    device: { deviceType: "desktop" },
    options: {
        // Here go the DropDownBox properties
    }
});

Angular

TypeScript

import DropDownBox, { Properties } from "devextreme/ui/drop_down_box";
// ...
export class AppComponent {
    constructor () {
        DropDownBox.defaultOptions<Properties>({
            device: { deviceType: "desktop" },
            options: {
                // Here go the DropDownBox properties
            }
        });
    }
}

Vue

<template>
    <div>
        <DxDropDownBox id="dropDownBox1" />
        <DxDropDownBox id="dropDownBox2" />
    </div>
</template>
<script>
import DxDropDownBox from "devextreme-vue/drop-down-box";
import DropDownBox from "devextreme/ui/drop_down_box";

DropDownBox.defaultOptions({
    device: { deviceType: "desktop" },
    options: {
        // Here go the DropDownBox properties
    }
});

export default {
    components: {
        DxDropDownBox
    }
}
</script>

React

import dxDropDownBox from "devextreme/ui/drop_down_box";
import DropDownBox from "devextreme-react/drop-down-box";

dxDropDownBox.defaultOptions({
    device: { deviceType: "desktop" },
    options: {
        // Here go the DropDownBox properties
    }
});

export default function App() {
    return (
        <div>
            <DropDownBox id="dropDownBox1" />
            <DropDownBox id="dropDownBox2" />
        </div>
    )
}

dispose()

Disposes of all the resources allocated to the DropDownBox instance.

jQuery

After calling this method, remove the DOM element associated with the UI component:

JavaScript

$("#myDropDownBox").dxDropDownBox("dispose");
$("#myDropDownBox").remove();

Angular

Use conditional rendering instead of this method:

app.component.html

<dx-drop-down-box ...
    *ngIf="condition">
</dx-drop-down-box>

Vue

Use conditional rendering instead of this method:

App.vue

<template>
    <DxDropDownBox ...
        v-if="condition">
    </DxDropDownBox>
</template>

<script>
import DxDropDownBox from 'devextreme-vue/drop-down-box';

export default {
    components: {
        DxDropDownBox
    }
}
</script>

React

Use conditional rendering instead of this method:

App.js

import React from 'react';

import DropDownBox from 'devextreme-react/drop-down-box';

function DxDropDownBox(props) {
    if (!props.shouldRender) {
        return null;
    }

    return (
        <DropDownBox ... >    
        </DropDownBox>
    );
}

class App extends React.Component {
    render() {
        return (
            <DxDropDownBox shouldRender="condition" />
        );
    }
}
export default App;

element()

Gets the root UI component element.

Return Value:

HTMLElement | jQuery

An HTML element or a jQuery element when you use jQuery.

jQuery

Call Methods

Angular

Call Methods

Vue

Call Methods

React

Call Methods

endUpdate()

Refreshes the UI component after a call of the beginUpdate() method.

Main article: beginUpdate()

jQuery

Call Methods

Angular

Call Methods

Vue

Call Methods

React

Call Methods

field()

Gets the UI component's <input> element.

Return Value:

HTMLElement | jQuery

An HTML element or a jQuery element when you use jQuery.

jQuery

Call Methods

Angular

Call Methods

Vue

Call Methods

React

Call Methods

focus()

Sets focus to the input element representing the UI component.

jQuery

Call Methods

Angular

Call Methods

Vue

Call Methods

React

Call Methods

getButton(name)

Gets an instance of a custom action button.

Parameters:

name:

String

The button's name.

Return Value:

Button

| undefined

The Button UI component's instance.

Use the returned button instance to call the Button UI component's methods, for example, focus():

jQuery

index.js

const myCustomButton = $("#dropDownBoxContainer").dxDropDownBox("getButton", "myCustomButton");
myCustomButton.focus();

Angular

app.component.ts

app.component.html

import { Component, ViewChild } from '@angular/core';
import { DxDropDownBoxComponent } from 'devextreme-angular';

@Component({
    selector: 'app-root',
    templateUrl: './app.component.html',
    styleUrls: ['./app.component.css']
})
export class AppComponent {
    @ViewChild('dropDownBoxRef', { static: false }) dropDownBox: DxDropDownBoxComponent;
    // Prior to Angular 8
    // @ViewChild('dropDownBoxRef') dropDownBox: DxDropDownBoxComponent;

    setFocus() {
        this.dropDownBox.instance.getButton('myCustomButton').focus();
    }
}

<dx-drop-down-box #dropDownBoxRef ... >
</dx-drop-down-box>

Vue

App.vue

<template>
    <DxDropDownBox ...
        :ref="dropDownBoxRef">
    </DxDropDownBox>
</template>

<script>
import 'devextreme/dist/css/dx.light.css';

import DxDropDownBox from 'devextreme-vue/drop-down-box';

export default {
    components: {
        DxDropDownBox
    },

    data() {
        return {
            dropDownBoxRef
        }
    },

    methods: {
        setFocus() {
            this.dropDownBox.getButton('myCustomButton').focus();
        }
    },

    computed: {
        dropDownBox: function() {
            return this.$refs[dropDownBoxRef].instance;
        }
    }
}
</script>

React

App.js

import React from 'react';

import 'devextreme/dist/css/dx.light.css';

import DropDownBox from 'devextreme-react/drop-down-box';

class App extends React.Component {
    constructor(props) {
        super(props);

        this.dropDownBoxRef = React.createRef();

        this.setFocus = () => {
            this.dropDownBox.getButton('myCustomButton').focus();
        };
    }

    get dropDownBox() {
        return this.dropDownBoxRef.current.instance;
    }

    render() {
        return (
            <DropDownBox ...
                ref={this.dropDownBoxRef}>
            </DropDownBox>
        );
    }
}
export default App;

getDataSource()

Gets the DataSource instance.

Return Value:

DataSource

The DataSource instance.

NOTE

This method returns the DataSource instance even if the UI component's dataSource property was given a simple array.

jQuery

Call Methods

Angular

Call Methods

Vue

Call Methods

React

Call Methods

getInstance(element)

Gets the instance of a UI component found using its DOM node.

Parameters:

element:

Element

|

jQuery

The UI component's container.

Return Value:

Object

The UI component's instance.

getInstance is a static method that the UI component class supports. The following code demonstrates how to get the DropDownBox instance found in an element with the myDropDownBox ID:

// Modular approach
import DropDownBox from "devextreme/ui/drop_down_box";
...
let element = document.getElementById("myDropDownBox");
let instance = DropDownBox.getInstance(element) as DropDownBox;

// Non-modular approach
let element = document.getElementById("myDropDownBox");
let instance = DevExpress.ui.dxDropDownBox.getInstance(element);