TreeViewItem Class
A Tree View dashboard item that allows end users to filter other dashboard items.
Declaration
export class TreeViewItem extends FilterElementItemBaseRemarks
The Tree View dashboard item displays values hierarchically and allows end users to filter other dashboard items by selecting parent/child values.
The Tree View dashboard item does not support self-reference or parent-child hierarchies. The number of dimensions added to the Tree View item determines the number of levels in the hierarchy. Each level contains unique values from the corresponding level dimension. Values in each level are grouped by values in the previous dimension.
Refer to Filter Elements Overview to learn more about filter elements.
Example
The following example shows how to create the Tree View dashboard item, bind it to data and add to the existing dashboard.
Create data items (dimensions) and use the DataItem.dataMember property to bind them to the existing data source’s columns. Then use the created dimensions in the dashboard item to bind it to data.
After you add the created dashboard item to the Dashboard.items collection, call the Dashboard.rebuildLayout method to rebuild the dashboard layout and display changes.
// Use the line below for a modular approach:
// import * as Model from 'devexpress-dashboard/model'
// Use the line below for an approach with global namespaces:
// var Model = DevExpress.Dashboard.Model;
// ...
public creatTreeView() {
// Create data items for the TreeView.
var treeViewYear = new Model.Dimension();
treeViewYear.dataMember("OrderDate");
treeViewYear.dateTimeGroupInterval('Year');
var treeViewMonth = new Model.Dimension();
treeViewMonth.dataMember("OrderDate");
treeViewMonth.dateTimeGroupInterval('Month');
// Create TreeView
var treeViewItem = new Model.TreeViewItem();
treeViewItem.name('treeView');
treeViewItem.dataSource(sqlDataSource.componentName());
treeViewItem.dataMember(sqlDataSource.queries()[0].name());
treeViewItem.filterDimensions.push(treeViewYear);
treeViewItem.filterDimensions.push(treeViewMonth);
treeViewItem.autoExpand(true);
control.dashboard().items.push(treeViewItem);
// ...
control.dashboard().rebuildLayout();
}
Inherited Members
Inheritance
constructor
Initializes a new instance of the TreeViewItem class.
Declaration
constructor(
dashboardItemJSON?: any,
serializer?: DevExpress.Analytics.Utils.ModelSerializer
)Parameters
| Name | Type | Description |
|---|---|---|
| dashboardItemJSON | any | A JSON object used for dashboard deserialization. Do not pass this parameter directly. |
| serializer | ModelSerializer | An object used for dashboard deserialization. Do not pass this parameter directly. |
Properties
autoExpand Property
Specifies whether tree view nodes are expanded by default.
Declaration
autoExpand: ko.Observable<boolean>Property Value
| Type | Description |
|---|---|
| Observable<boolean> | true, to expand tree view nodes by default; otherwise, false. |