JavaScript/jQuery TreeView Methods
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
collapseItem(itemData)
A Promise that is resolved after the item is collapsed and rejected if the item is nonexistent or disabled.
It is a native Promise or a jQuery.Promise when you use jQuery.
collapseItem(itemElement)
A Promise that is resolved after the item is collapsed and rejected if the item is nonexistent or disabled.
It is a native Promise or a jQuery.Promise when you use jQuery.
collapseItem(key)
A Promise that is resolved after the item is collapsed and rejected if the item is nonexistent or disabled.
It is a native Promise or a jQuery.Promise when you use jQuery.
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 TreeView UI component in an application executed on the desktop.
jQuery
DevExpress.ui.dxTreeView.defaultOptions({ device: { deviceType: "desktop" }, options: { // Here go the TreeView properties } });
Angular
import TreeView from "devextreme/ui/tree_view"; // ... export class AppComponent { constructor () { TreeView.defaultOptions({ device: { deviceType: "desktop" }, options: { // Here go the TreeView properties } }); } }
Vue
<template> <div> <DxTreeView id="treeView1" /> <DxTreeView id="treeView2" /> </div> </template> <script> import DxTreeView from "devextreme-vue/tree-view"; import TreeView from "devextreme/ui/tree_view"; TreeView.defaultOptions({ device: { deviceType: "desktop" }, options: { // Here go the TreeView properties } }); export default { components: { DxTreeView } } </script>
React
import React, {useEffect} from "react"; import dxTreeView from "devextreme/ui/tree_view"; import TreeView from "devextreme-react/tree-view"; export default function App() { useEffect(() => { dxTreeView.defaultOptions({ device: { deviceType: "desktop" }, options: { // Here go the TreeView properties } }) }); return ( <div> <TreeView id="treeView1" /> <TreeView id="treeView2" /> </div> ) }
dispose()
After calling this method, remove the DOM element associated with the UI component:
$("#myTreeView").dxTreeView("dispose"); $("#myTreeView").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-tree-view ... *ngIf="condition"> </dx-tree-view>
Vue
<template> <DxTreeView ... v-if="condition"> </DxTreeView> </template> <script> import DxTreeView from 'devextreme-vue/tree-view'; export default { components: { DxTreeView } } </script>
React
import React from 'react'; import TreeView from 'devextreme-react/tree-view'; function DxTreeView(props) { if (!props.shouldRender) { return null; } return ( <TreeView ... > </TreeView> ); } class App extends React.Component { render() { return ( <DxTreeView shouldRender="condition" /> ); } } export default App;
See Also
expandAll()
Expands all items. If you load items on demand, this method expands only the loaded items.
expandItem(itemData)
A Promise that is resolved after the item is expanded and rejected if the item is nonexistent or disabled.
It is a native Promise or a jQuery.Promise when you use jQuery.
expandItem(itemElement)
A Promise that is resolved after the item is expanded and rejected if the item is nonexistent or disabled.
It is a native Promise or a jQuery.Promise when you use jQuery.
expandItem(key)
A Promise that is resolved after the item is expanded and rejected if the item is nonexistent or disabled.
It is a native Promise or a jQuery.Promise when you use jQuery.
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 TreeView instance found in an element with the myTreeView
ID:
// Modular approach import TreeView from "devextreme/ui/tree_view"; ... let element = document.getElementById("myTreeView"); let instance = TreeView.getInstance(element) as TreeView; // Non-modular approach let element = document.getElementById("myTreeView"); let instance = DevExpress.ui.dxTreeView.getInstance(element);
See Also
getSelectedNodeKeys()
Array<any>
See Also
- selectByClick
- showCheckBoxesMode
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
getSelectedNodes()
jQuery
const selectedNodes = $("#treeViewContainer").dxTreeView("getSelectedNodes");
Angular
import { Component, ViewChild } from '@angular/core'; import { DxTreeViewComponent } from 'devextreme-angular'; @Component({ selector: 'app-root', templateUrl: './app.component.html', styleUrls: ['./app.component.css'] }) export class AppComponent { @ViewChild('treeViewRef', { static: false }) treeView: DxTreeViewComponent; // Prior to Angular 8 // @ViewChild('treeViewRef') treeView: DxTreeViewComponent; selectedNodes = []; getSelectedNodes() { this.selectedNodes = this.treeView.instance.getSelectedNodes(); } }
<dx-tree-view ... #treeViewRef> </dx-tree-view>
import { BrowserModule } from '@angular/platform-browser'; import { NgModule } from '@angular/core'; import { AppComponent } from './app.component'; import { DxTreeViewModule } from 'devextreme-angular'; @NgModule({ declarations: [ AppComponent ], imports: [ BrowserModule, DxTreeViewModule ], providers: [ ], bootstrap: [AppComponent] }) export class AppModule { }
Vue
<template> <DxTreeView ... :ref="treeViewRef"> </DxTreeView> </template> <script> import 'devextreme/dist/css/dx.common.css'; import 'devextreme/dist/css/dx.light.css'; import DxTreeView from 'devextreme-vue/tree-view'; export default { components: { DxTreeView }, data() { return { treeViewRef, selectedNodes: [] } }, computed: { treeView: function() { return this.$refs[treeViewRef].instance; } }, methods: { getSelectedNodes() { this.selectedNodes = this.treeView.getSelectedNodes(); } } } </script>
React
import React from 'react'; import 'devextreme/dist/css/dx.common.css'; import 'devextreme/dist/css/dx.light.css'; import TreeView from 'devextreme-react/tree-view'; class App extends React.Component { constructor(props) { super(props); this.treeViewRef = React.createRef(); this.selectedNodes = []; this.getSelectedNodes = () => { this.selectedNodes = this.treeView.getSelectedNodes(); } } get treeView() { return this.treeViewRef.current.instance; } render() { return ( <TreeView ... ref={this.treeViewRef}> </TreeView> ); } } export default App;
See Also
- selectByClick
- showCheckBoxesMode
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
registerKeyHandler(key, handler)
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
scrollToItem(itemData)
A Promise that is resolved after the content is scrolled to the target item and rejected if the item is nonexsistent or nested in a collapsed and disabled node.
It is a native Promise or a jQuery.Promise when you use jQuery.
scrollToItem(itemElement)
A Promise that is resolved after the content is scrolled to the target item and rejected if the item is nonexsistent or nested in a collapsed and disabled node.
It is a native Promise or a jQuery.Promise when you use jQuery.
scrollToItem(key)
A Promise that is resolved after the content is scrolled to the target item and rejected if the item is nonexsistent or nested in a collapsed and disabled node.
It is a native Promise or a jQuery.Promise when you use jQuery.
selectAll()
This method has the following specificities:
Only loaded nodes can be selected. Take this specificity into account if nodes are loaded on demand (for example, if you use the virtual mode or createChildren function).
If searching is applied, only the nodes that satisfy the search condition can be selected.
See Also
- selectByClick
- showCheckBoxesMode
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
selectItem(itemData)
This method has the following specificities:
Only loaded nodes can be selected. Take this specificity into account if nodes are loaded on demand (for example, if you use the virtual mode or createChildren function).
If searching is applied, only the nodes that satisfy the search condition can be selected.
See Also
- selectByClick
- showCheckBoxesMode
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
selectItem(itemElement)
This method has the following specificities:
Only loaded nodes can be selected. Take this specificity into account if nodes are loaded on demand (for example, if you use the virtual mode or createChildren function).
If searching is applied, only the nodes that satisfy the search condition can be selected.
See Also
- selectByClick
- showCheckBoxesMode
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
selectItem(key)
This method has the following specificities:
Only loaded nodes can be selected. Take this specificity into account if nodes are loaded on demand (for example, if you use the virtual mode or createChildren function).
If searching is applied, only the nodes that satisfy the search condition can be selected.
See Also
- selectByClick
- showCheckBoxesMode
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
unselectAll()
This method has the following specificities:
The selection of only loaded nodes can be canceled. Take this specificity into account if nodes are loaded on demand (for example, if you use the virtual mode or createChildren function).
If searching is applied, this method cancels the selection of only those nodes that satisfy the search condition.
See Also
- selectByClick
- showCheckBoxesMode
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
unselectItem(itemData)
This method has the following specificities:
The selection of only loaded nodes can be canceled. Take this specificity into account if nodes are loaded on demand (for example, if you use the virtual mode or createChildren function).
If searching is applied, this method cancels the selection of only those nodes that satisfy the search condition.
See Also
- selectByClick
- showCheckBoxesMode
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
unselectItem(itemElement)
This method has the following specificities:
The selection of only loaded nodes can be canceled. Take this specificity into account if nodes are loaded on demand (for example, if you use the virtual mode or createChildren function).
If searching is applied, this method cancels the selection of only those nodes that satisfy the search condition.
See Also
- selectByClick
- showCheckBoxesMode
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
unselectItem(key)
This method has the following specificities:
The selection of only loaded nodes can be canceled. Take this specificity into account if nodes are loaded on demand (for example, if you use the virtual mode or createChildren function).
If searching is applied, this method cancels the selection of only those nodes that satisfy the search condition.
See Also
- selectByClick
- showCheckBoxesMode
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout
updateDimensions()
A Promise that is resolved if the UI component is updated and rejected otherwise. It is a native Promise or a jQuery.Promise when you use jQuery.