JavaScript/jQuery Menu Methods

This section describes members used to manipulate the UI component.

beginUpdate()

Postpones rendering that can negatively affect performance until the endUpdate() method is called.

The beginUpdate() and endUpdate() methods reduce the number of renders in cases where extra rendering can negatively affect performance.

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 Menu UI component in an application executed on the desktop.

jQuery

JavaScript

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

Angular

TypeScript

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

Vue

<template>
    <div>
        <DxMenu id="menu1" />
        <DxMenu id="menu2" />
    </div>
</template>
<script>
import DxMenu from "devextreme-vue/menu";
import Menu from "devextreme/ui/menu";

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

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

React

import dxMenu from "devextreme/ui/menu";
import Menu from "devextreme-react/menu";

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

export default function App() {
    return (
        <div>
            <Menu id="menu1" />
            <Menu id="menu2" />
        </div>
    )
}

You can also set rules for multiple device types:

jQuery

JavaScript

const devicesConfig = [
    { deviceType: 'desktop' },
    { deviceType: 'tablet' },
    { deviceType: 'phone' },
];

devicesConfig.forEach(deviceConfig => {
    DevExpress.ui.dxMenu.defaultOptions({ 
        device: deviceConfig,
        options: {
            // Here go the Menu properties
        }
    });
});

Angular

TypeScript

import Menu, { Properties } from "devextreme/ui/menu";
// ...
export class AppComponent {
    constructor () {
        const devicesConfig = [
            { deviceType: 'desktop' },
            { deviceType: 'tablet' },
            { deviceType: 'phone' },
        ];

        devicesConfig.forEach(deviceConfig => {
            Menu.defaultOptions<Properties>({
                device: deviceConfig,
                options: {
                    // Here go the Menu properties
                }
            });
        });
    }
}

Vue

<template>
    <div>
        <DxMenu />
    </div>
</template>
<script>
import DxMenu from "devextreme-vue/menu";
import Menu from "devextreme/ui/menu";

const devicesConfig = [
    { deviceType: 'desktop' },
    { deviceType: 'tablet' },
    { deviceType: 'phone' },
];

devicesConfig.forEach(deviceConfig => {
    Menu.defaultOptions({
        device: deviceConfig,
        options: {
            // Here go the Menu properties
        }
    });
});

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

React

import dxMenu from "devextreme/ui/menu";
import Menu from "devextreme-react/menu";

const devicesConfig = [
    { deviceType: 'desktop' },
    { deviceType: 'tablet' },
    { deviceType: 'phone' },
];

devicesConfig.forEach(deviceConfig => {
    dxMenu.defaultOptions({
        device: deviceConfig,
        options: {
            // Here go the Menu properties
        }
    });
});

export default function App() {
    return (
        <div>
            <Menu />
        </div>
    )
}

dispose()

Disposes of all the resources allocated to the Menu instance.

jQuery

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

JavaScript

$("#myMenu").dxMenu("dispose");
$("#myMenu").remove();

Angular

Use conditional rendering instead of this method:

app.component.html

<dx-menu ...
    *ngIf="condition">
</dx-menu>

Vue

Use conditional rendering instead of this method:

App.vue

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

<script>
import DxMenu from 'devextreme-vue/menu';

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

React

Use conditional rendering instead of this method:

App.js

import React from 'react';

import Menu from 'devextreme-react/menu';

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

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

class App extends React.Component {
    render() {
        return (
            <DxMenu 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

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Angular

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Vue

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React

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endUpdate()

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

The beginUpdate() and endUpdate() methods reduce the number of renders in cases where extra rendering can negatively affect performance.

jQuery

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Angular

Call Methods

Vue

Call Methods

React

Call Methods

focus()

Sets focus on the UI component.

jQuery

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Angular

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Vue

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React

Call Methods

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.

View on GitHub

jQuery

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Angular

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Vue

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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 Menu instance found in an element with the myMenu ID:

// Modular approach
import Menu from "devextreme/ui/menu";
...
let element = document.getElementById("myMenu");
let instance = Menu.getInstance(element) as Menu;

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