JavaScript/jQuery TreeView API
The TreeView UI component is a tree-like representation of textual data.
See Also
- Set Up DevExtreme: Angular | Vue | React | jQuery | AngularJS | Knockout | ASP.NET MVC 5 | ASP.NET Core
- Configure a Widget: Angular | Vue | React | jQuery | AngularJS | Knockout | ASP.NET MVC 5 | ASP.NET Core
Options
An object defining configuration properties for the TreeView UI component.
| Name | Description |
|---|---|
| accessKey | Specifies the shortcut key that sets focus on the UI component. |
| activeStateEnabled | Specifies whether or not the UI component changes its state when interacting with a user. |
| animationEnabled | Specifies whether or not to animate item collapsing and expanding. |
| createChildren | Allows you to load nodes on demand. |
| dataSource | Binds the UI component to data. |
| dataStructure | Notifies the UI component of the used data structure. |
| disabled | Specifies whether the UI component responds to user interaction. |
| disabledExpr | Specifies the name of the data source item field whose value defines whether or not the corresponding UI component item is disabled. |
| displayExpr | Specifies the data field whose values should be displayed. |
| elementAttr | Specifies the global attributes to be attached to the UI component's container element. |
| expandAllEnabled | Specifies whether or not a user can expand all tree view items by the "*" hot key. |
| expandedExpr | Specifies which data source field specifies whether an item is expanded. |
| expandEvent | Specifies the event on which to expand/collapse a node. |
| expandNodesRecursive | Specifies whether or not all parent nodes of an initially expanded node are displayed expanded. |
| focusStateEnabled | Specifies whether the UI component can be focused using keyboard navigation. |
| hasItemsExpr | Specifies the name of the data source item field whose value defines whether or not the corresponding node includes child nodes. |
| height | Specifies the UI component's height. |
| hint | Specifies text for a hint that appears when a user pauses on the UI component. |
| hoverStateEnabled | Specifies whether the UI component changes its state when a user pauses on it. |
| itemComponent | An alias for the itemTemplate property specified in React. Accepts a custom component. Refer to Using a Custom Component for more information. |
| itemHoldTimeout | The time period in milliseconds before the onItemHold event is raised. |
| itemRender | An alias for the itemTemplate property specified in React. Accepts a rendering function. Refer to Using a Rendering Function for more information. |
| items | An array of items displayed by the UI component. |
| itemsExpr | Specifies which data field contains nested items. Applies only if the dataStructure property is "tree". |
| itemTemplate | Specifies a custom template for items. |
| keyExpr | Specifies which data field provides keys for TreeView items. |
| noDataText | The text or HTML markup displayed by the UI component if the item collection is empty. |
| onContentReady | A function that is executed when the UI component's content is ready and each time the content is changed. |
| onDisposing | A function that is executed before the UI component is disposed of. |
| onInitialized | A function used in JavaScript frameworks to save the UI component instance. |
| onItemClick | A function that is executed when a collection item is clicked or tapped. |
| onItemCollapsed | A function that is executed when a tree view item is collapsed. |
| onItemContextMenu | A function that is executed when a collection item is right-clicked or pressed. |
| onItemExpanded | A function that is executed when a tree view item is expanded. |
| onItemHold | A function that is executed when a collection item has been held for a specified period. |
| onItemRendered | A function that is executed after a collection item is rendered. |
| onItemSelectionChanged | A function that is executed when a single TreeView item is selected or selection is canceled. |
| onOptionChanged | A function that is executed after a UI component property is changed. |
| onSelectAllValueChanged | A function that is executed when the "Select All" check box value is changed. Applies only if showCheckBoxesMode is "selectAll" and selectionMode is "multiple". |
| onSelectionChanged | A function that is executed when a TreeView item is selected or selection is canceled. |
| parentIdExpr | Specifies the name of the data source item field for holding the parent key of the corresponding node. |
| rootValue | Specifies the parent ID value of the root item. |
| rtlEnabled | Switches the UI component to a right-to-left representation. |
| scrollDirection | A string value specifying available scrolling directions. |
| searchEditorOptions | Configures the search panel. |
| searchEnabled | Specifies whether the search panel is visible. |
| searchExpr | Specifies a data object's field name or an expression whose value is compared to the search string. |
| searchMode | Specifies a comparison operation used to search UI component items. |
| searchTimeout | Specifies a delay in milliseconds between when a user finishes typing, and the search is executed. |
| searchValue | Specifies the current search string. |
| selectAllText | Specifies the text displayed at the "Select All" check box. |
| selectByClick | Specifies whether an item becomes selected if a user clicks it. |
| selectedExpr | Specifies the name of the data source item field whose value defines whether or not the corresponding UI component items is selected. |
| selectionMode | Specifies item selection mode. Applies only if selection is enabled. |
| selectNodesRecursive | Specifies whether all child nodes should be selected when their parent node is selected. Applies only if the selectionMode is "multiple". |
| showCheckBoxesMode | Specifies the checkbox display mode. |
| tabIndex | Specifies the number of the element when the Tab key is used for navigating. |
| virtualModeEnabled | Enables the virtual mode in which nodes are loaded on demand. Use it to enhance the performance on large datasets. |
| visible | Specifies whether the UI component is visible. |
| width | Specifies the UI component's width. |
See Also
- Configure a Widget: Angular | Vue | React | jQuery | AngularJS | Knockout | ASP.NET MVC 5 | ASP.NET Core
Methods
This section describes members used to manipulate the UI component.
| Name | Description |
|---|---|
| beginUpdate() | Prevents the UI component from refreshing until the endUpdate() method is called. |
| collapseAll() | Collapses all items. |
| collapseItem(itemData) | Collapses an item with a specific key. |
| collapseItem(itemElement) | Collapses an item found using its DOM node. |
| collapseItem(key) | Collapses an item with a specific key. |
| defaultOptions(rule) | Specifies the device-dependent default configuration properties for this component. |
| dispose() | Disposes of all the resources allocated to the TreeView instance. |
| element() | Gets the root UI component element. |
| endUpdate() | Refreshes the UI component after a call of the beginUpdate() method. |
| expandAll() | Expands all items. If you load items on demand, this method expands only the loaded items. |
| expandItem(itemData) | Expands an item found using its data object. |
| expandItem(itemElement) | Expands an item found using its DOM node. |
| expandItem(key) | Expands an item with a specific key. |
| focus() | Sets focus on the UI component. |
| getDataSource() | Gets the DataSource instance. |
| getInstance(element) | Gets the instance of a UI component found using its DOM node. |
| getNodes() | Gets all nodes. |
| getSelectedNodeKeys() | Gets the keys of selected nodes. |
| getSelectedNodes() | Gets selected nodes. |
| instance() | Gets the UI component's instance. Use it to access other methods of the UI component. |
| off(eventName) | Detaches all event handlers from a single event. |
| off(eventName, eventHandler) | Detaches a particular event handler from a single event. |
| on(eventName, eventHandler) | Subscribes to an event. |
| on(events) | Subscribes to events. |
| option() | Gets all UI component properties. |
| option(optionName) | Gets the value of a single property. |
| option(optionName, optionValue) | Updates the value of a single property. |
| option(options) | Updates the values of several properties. |
| registerKeyHandler(key, handler) | Registers a handler to be executed when a user presses a specific key. |
| repaint() | Repaints the UI component without reloading data. Call it to update the UI component's markup. |
| resetOption(optionName) | Resets an property to its default value. |
| scrollToItem(itemData) | Scrolls the content to an item found using its data. |
| scrollToItem(itemElement) | Scrolls the content to an item found using its DOM node. |
| scrollToItem(key) | Scrolls the content to an item found using its key. |
| selectAll() | Selects all nodes. |
| selectItem(itemData) | Selects a node found using its data object. |
| selectItem(itemElement) | Selects a TreeView node found using its DOM node. |
| selectItem(key) | Selects a node with a specific key. |
| unselectAll() | Cancels the selection of all nodes. |
| unselectItem(itemData) | Cancels the selection of a node found using its data object. |
| unselectItem(itemElement) | Cancels the selection of a TreeView node found using its DOM node. |
| unselectItem(key) | Cancels the selection of a node with a specific key. |
| updateDimensions() | Updates the tree view scrollbars according to the current size of the UI component content. |
See Also
- Call Methods: Angular | Vue | React | jQuery | AngularJS | Knockout | ASP.NET MVC 5 | ASP.NET Core
Events
This section describes events fired by this UI component.
| Name | Description |
|---|---|
| contentReady | Raised when the UI component's content is ready. |
| disposing | Raised before the UI component is disposed of. |
| initialized | Raised only once, after the UI component is initialized. |
| itemClick | Raised when a collection item is clicked or tapped. |
| itemCollapsed | Raised when a tree view item is collapsed. |
| itemContextMenu | Raised when a collection item is right-clicked or pressed. |
| itemExpanded | Raised when a tree view item is expanded. |
| itemHold | Raised when a collection item has been held for a specified period. |
| itemRendered | Raised after a collection item is rendered. |
| itemSelectionChanged | Raised when a tree view item is selected or selection is canceled. |
| optionChanged | Raised after a UI component property is changed. |
| selectAllValueChanged | Raised when the "Select All" check box value is changed. |
| selectionChanged | Raised when a tree view item is selected or selection is canceled. |
See Also
- Handle Events: Angular | Vue | React | jQuery | AngularJS | Knockout | ASP.NET MVC 5 | ASP.NET Core
Node
A TreeView node.
This section describes the contents of a TreeView node object. Such objects can be accessed using the getNodes() method and within functions handling the events whose name begins with item....