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)
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
DevExpress.ui.dxMenu.defaultOptions({
device: { deviceType: "desktop" },
options: {
// Here go the Menu properties
}
});Angular
import Menu from "devextreme/ui/menu";
// ...
export class AppComponent {
constructor () {
Menu.defaultOptions({
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 React, {useEffect} from "react";
import dxMenu from "devextreme/ui/menu";
import Menu from "devextreme-react/menu";
export default function App() {
useEffect(() => {
dxMenu.defaultOptions({
device: { deviceType: "desktop" },
options: {
// Here go the Menu properties
}
})
});
return (
<div>
<Menu id="menu1" />
<Menu id="menu2" />
</div>
)
}dispose()
After calling this method, remove the DOM element associated with the UI component:
$("#myMenu").dxMenu("dispose");
$("#myMenu").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
<dx-menu ...
*ngIf="condition">
</dx-menu>Vue
<template>
<DxMenu ...
v-if="condition">
</DxMenu>
</template>
<script>
import DxMenu from 'devextreme-vue/menu';
export default {
components: {
DxMenu
}
}
</script>React
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;See Also
getDataSource()
Gets the DataSource instance.
See Also
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
- Data Layer - Overview
- Data Layer - DataSource Examples
getInstance(element)
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);See Also
registerKeyHandler(key, handler)
A handler. Accepts the keydown event as the argument. It is a EventObject 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.