Methods

This section describes members used to manipulate the UI component.

See Also

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.

See Also

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

|

Array<Device>

|

Function

Device parameters.
When specifying 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 Gallery UI component in an application executed on the desktop.

jQuery
JavaScript
DevExpress.ui.dxGallery.defaultOptions({ 
    device: { deviceType: "desktop" },
    options: {
        // Here go the Gallery properties
    }
});
Angular
TypeScript
import Gallery from "devextreme/ui/gallery";
// ...
export class AppComponent {
    constructor () {
        Gallery.defaultOptions({
            device: { deviceType: "desktop" },
            options: {
                // Here go the Gallery properties
            }
        });
    }
}
Vue
<template>
    <div>
        <DxGallery id="gallery1" />
        <DxGallery id="gallery2" />
    </div>
</template>
<script>
import DxGallery from "devextreme-vue/gallery";
import Gallery from "devextreme/ui/gallery";

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

export default {
    components: {
        DxGallery
    }
}
</script>
React
import React from "react";
import dxGallery from "devextreme/ui/gallery";
import Gallery from "devextreme-react/gallery";

class App extends React.Component {
    render () {
        dxGallery.defaultOptions({
            device: { deviceType: "desktop" },
            options: {
                // Here go the Gallery properties
            }
        })
        return (
            <div>
                <Gallery id="gallery1" />
                <Gallery id="gallery2" />
            </div>
        )
    }
}

export default App;

dispose()

Disposes of all the resources allocated to the Gallery instance.

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

JavaScript
$("#myGallery").dxGallery("dispose");
$("#myGallery").remove();

Use this method only if the UI component was created with jQuery or pure JavaScript. In Angular, Vue, and React, use conditional rendering:

Angular
app.component.html
<dx-gallery ...
    *ngIf="condition">
</dx-gallery>
Vue
App.vue
<template>
    <DxGallery ...
        v-if="condition">
    </DxGallery>
</template>

<script>
import DxGallery from 'devextreme-vue/gallery';

export default {
    components: {
        DxGallery
    }
}
</script>
React
App.js
import React from 'react';

import Gallery from 'devextreme-react/gallery';

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

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

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

element()

Gets the root UI component element.

Return Value:

HTMLElement or jQuery

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

See Also

endUpdate()

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

Main article: beginUpdate()

See Also

focus()

Sets focus on the UI component.

See Also

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.
See Also

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 Gallery instance found in an element with the myGallery ID:

// Modular approach
import Gallery from "devextreme/ui/gallery";
...
let element = document.getElementById("myGallery");
let instance = Gallery.getInstance(element) as Gallery;

// Non-modular approach
let element = document.getElementById("myGallery");
let instance = DevExpress.ui.dxGallery.getInstance(element);
See Also

goToItem(itemIndex, animation)

Shows a specific image.

Parameters:
itemIndex:

Number

The index of the image in the dataSource.

animation:

Boolean

Specifies whether switching to the image should be animated.

Return Value:

Promise<void> (jQuery or native)

A Promise that is resolved after the image is shown. It is a native Promise or a jQuery.Promise when you use jQuery.

See Also

instance()

Gets the UI component's instance. Use it to access other methods of the UI component.

Return Value:

Gallery

This UI component's instance.

See Also

nextItem(animation)

Shows the next image.

Parameters:
animation:

Boolean

Specifies whether switching to the image should be animated.

Return Value:

Promise<void> (jQuery or native)

A Promise that is resolved after the image is shown. It is a native Promise or a jQuery.Promise when you use jQuery.

If the current item is the last item in the gallery, the method behavior depends on the loop property value. If loop is set to true, the first item is shown. Otherwise, the method does nothing.

See Also

off(eventName)

Detaches all event handlers from a single event.

Parameters:
eventName:

String

The event's name.

Return Value:

Gallery

The object for which this method is called.

See Also

off(eventName, eventHandler)

Detaches a particular event handler from a single event.

Parameters:
eventName:

String

The event's name.

eventHandler:

Function

The event's handler.

Return Value:

Gallery

The object for which this method is called.

See Also

on(eventName, eventHandler)

Subscribes to an event.

Parameters:
eventName:

String

The event's name.

eventHandler:

Function

The event's handler.

Return Value:

Gallery

The object for which this method is called.

Use this method to subscribe to one of the events listed in the Events section.

See Also

on(events)

Subscribes to events.

Parameters:
events:

Object

Events with their handlers: { "eventName1": handler1, "eventName2": handler2, ...}

Return Value:

Gallery

The object for which this method is called.

Use this method to subscribe to several events with one method call. Available events are listed in the Events section.

See Also

option()

Return Value:

Object

The UI component's properties.

option(optionName)

Gets the value of a single property.

Parameters:
optionName:

String

The property's name or full path.

Return Value: any

This property's value.

option(optionName, optionValue)

Updates the value of a single property.

Parameters:
optionName:

String

The property's name or full path.

optionValue: any

This property's new value.

option(options)

Updates the values of several properties.

Parameters:
options:

Object

Options with their new values.

prevItem(animation)

Shows the previous image.

Parameters:
animation:

Boolean

Specifies whether switching to the image should be animated.

Return Value:

Promise<void> (jQuery or native)

A Promise that is resolved after the image is shown. It is a native Promise or a jQuery.Promise when you use jQuery.

If the current item is the first item in the gallery, the method behavior depends on the loop property value. If loop is set to true, the last item is shown. Otherwise, the method does nothing.

See Also

registerKeyHandler(key, handler)

Registers a handler to be executed when a user presses a specific key.

Parameters:
key:

String

A key.

handler:

Function

A handler. Accepts the keydown event as the argument. It is a dxEvent or a jQuery.Event when you use jQuery.

The key argument accepts one of the following values:

  • "backspace"
  • "tab"
  • "enter"
  • "escape"
  • "pageUp"
  • "pageDown"
  • "end"
  • "home"
  • "leftArrow"
  • "upArrow"
  • "rightArrow"
  • "downArrow"
  • "del"
  • "space"
  • "F"
  • "A"
  • "asterisk"
  • "minus"

A custom handler for a key cancels the default handler for this key.

See Also

repaint()

Repaints the UI component without reloading data. Call it to update the UI component's markup.

See Also

resetOption(optionName)

Resets an property to its default value.

Parameters:
optionName:

String

An property's name.

See Also