React Gantt Methods

This section describes methods that control the Gantt UI component.

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

Propertiesto 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 Gantt UI component in an application executed on the desktop.

jQuery
JavaScript
DevExpress.ui.dxGantt.defaultOptions({ 
    device: { deviceType: "desktop" },
    options: {
        // Here go the Gantt options
    }
});
Angular
TypeScript
import Gantt from "devextreme/ui/gantt";
// ...
export class AppComponent {
    constructor () {
        Gantt.defaultOptions({
            device: { deviceType: "desktop" },
            options: {
                // Here go the Gantt options
            }
        });
    }
}
Vue
<template>
    <div>
        <DxGantt id="gantt1" />
        <DxGantt id="gantt2" />
    </div>
</template>
<script>
import DxGantt from "devextreme-vue/gantt";
import Gantt from "devextreme/ui/gantt";

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

export default {
    components: {
        DxGantt
    }
}
</script>
React
import React from "react";
import dxGantt from "devextreme/ui/gantt";
import Gantt from "devextreme-react/gantt";

class App extends React.Component {
    render () {
        dxGantt.defaultOptions({
            device: { deviceType: "desktop" },
            options: {
                // Here go the Gantt options
            }
        })
        return (
            <div>
                <Gantt id="gantt1" />
                <Gantt id="gantt2" />
            </div>
        )
    }
}

export default App;

dispose()

Disposes of all the resources allocated to the Gantt instance.

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

JavaScript
$("#myGantt").dxGantt("dispose");
$("#myGantt").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-gantt ...
    *ngIf="condition">
</dx-gantt>
Vue
App.vue
<template>
    <DxGantt ...
        v-if="condition">
    </DxGantt>
</template>

<script>
import DxGantt from 'devextreme-vue/gantt';

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

import Gantt from 'devextreme-react/gantt';

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

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

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

element()

Gets the root UI component element.

Return Value:

HTMLElement | 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

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 Gantt instance found in an element with the myGantt ID:

// Modular approach
import Gantt from "devextreme/ui/gantt";
...
let element = document.getElementById("myGantt");
let instance = Gantt.getInstance(element) as Gantt;

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

instance()

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

Return Value:

Gantt

This UI component's instance.

See Also

off(eventName)

Detaches all event handlers from a single event.

Parameters:
eventName:

String

The event's name.

Return Value:

Gantt

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:

Gantt

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:

Gantt

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:

Gantt

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()

Gets all UI component properties.

Return Value:

Object

The UI component's properties.

See Also

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.

See Also

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.

See Also

option(options)

Updates the values of several properties.

Parameters:
options:

Object

Propertieswith their new values.

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