Angular TreeList API

The TreeList is a UI component that represents data from a local or remote source in the form of a multi-column tree view. This UI component offers such features as sorting, filtering, editing, selection, etc.

import { DxTreeListModule } from "devextreme-angular"
Selector: dx-tree-list

Configuration

An object defining configuration properties for the TreeList UI component.

Name Description
accessKey

Specifies the shortcut key that sets focus on the UI component.

activeStateEnabled

Specifies whether the UI component changes its visual state as a result of user interaction.

allowColumnReordering

Specifies whether a user can reorder columns.

allowColumnResizing

Specifies whether a user can resize columns.

autoExpandAll

Specifies whether all rows are expanded initially.

autoNavigateToFocusedRow

Automatically scrolls the component to the focused row when the focusedRowKey is changed.

cacheEnabled

Specifies whether data should be cached.

cellHintEnabled

Enables a hint that appears when a user hovers the mouse pointer over a cell with truncated content.

columnAutoWidth

Specifies whether columns should adjust their widths to the content.

columnChooser

Configures the column chooser.

columnFixing

Configures column fixing.

columnHidingEnabled

Specifies whether the UI component should hide columns to adapt to the screen or container size. Ignored if allowColumnResizing is true and columnResizingMode is "widget".

columnMinWidth

Specifies the minimum width of columns.

columnResizingMode

Specifies how the UI component resizes columns. Applies only if allowColumnResizing is true.

columns

Configures columns.

columnWidth

Specifies the width for all data columns. Has a lower priority than the column.width property.

customizeColumns

Customizes columns after they are created.

dataSource

Binds the UI component to data.

dataStructure

Notifies the UI component of the used data structure.

dateSerializationFormat

Specifies the format in which date-time values should be sent to the server.

disabled

Specifies whether the UI component responds to user interaction.

editing

Configures editing.

elementAttr

Specifies the global attributes to be attached to the UI component's container element.

errorRowEnabled

Indicates whether to show the error row.

expandedRowKeys

Specifies keys of the initially expanded rows.

expandNodesOnFiltering

Specifies whether nodes appear expanded or collapsed after filtering is applied.

filterBuilder

Configures the integrated filter builder.

filterBuilderPopup

Configures the popup in which the integrated filter builder is shown.

filterMode

Specifies whether filter and search results should include matching rows only, matching rows with ancestors, or matching rows with ancestors and descendants (full branch).

filterPanel

Configures the filter panel.

filterRow

Configures the filter row.

filterSyncEnabled

Specifies whether to synchronize the filter row, header filter, and filter builder. The synchronized filter expression is stored in the filterValue property.

filterValue

Specifies a filter expression.

focusedColumnIndex

The index of the column that contains the focused data cell. This index is taken from the columns array.

focusedRowEnabled

Specifies whether the focused row feature is enabled.

focusedRowIndex

Specifies or indicates the focused data row's index.

focusedRowKey

Specifies initially or currently focused grid row's key.

hasItemsExpr

Specifies which data field defines whether the node has children.

headerFilter

Configures the header filter feature.

height

Specifies the UI component's height.

highlightChanges

Specifies whether to highlight rows and cells with edited data. repaintChangesOnly should be true.

hint

Specifies text for a hint that appears when a user pauses on the UI component.

hoverStateEnabled

Specifies whether to highlight rows when a user moves the mouse pointer over them.

itemsExpr

Specifies which data field contains nested items. Set this property when your data has a hierarchical structure.

keyboardNavigation

Configures keyboard navigation.

keyExpr

Specifies the key property (or properties) that provide(s) key values to access data items. Each key value must be unique.

loadPanel

Configures the load panel.

noDataText

Specifies a text string shown when the TreeList does not display any data.

onAdaptiveDetailRowPreparing

A function that is executed before an adaptive detail row is rendered.

onCellClick

A function that is executed when a cell is clicked or tapped. Executed before onRowClick.

onCellDblClick

A function that is executed when a cell is double-clicked or double-tapped. Executed before onRowDblClick.

onCellHoverChanged

A function that is executed after the pointer enters or leaves a cell.

onCellPrepared

A function that is executed after a grid cell is created.

onContentReady

A function that is executed when the UI component is rendered and each time the component is repainted.

onContextMenuPreparing

A function that is executed before the context menu is rendered.

onDataErrorOccurred

A function that is executed when an error occurs in the data source.

onDisposing

A function that is executed before the UI component is disposed of.

onEditCanceled

A function that is executed after row changes are discarded.

onEditCanceling

A function that is executed when the edit operation is canceled, but row changes are not yet discarded.

onEditingStart

A function that is executed before a cell or row switches to the editing state.

onEditorPrepared

A function that is executed after an editor is created. Not executed for cells with an editCellTemplate.

onEditorPreparing

A function used to customize a cell's editor. Not executed for cells with an editCellTemplate.

onFocusedCellChanged

A function that is executed after the focused cell changes. Applies only to cells in data rows.

onFocusedCellChanging

A function that is executed before the focused cell changes. Applies only to cells in data rows.

onFocusedRowChanged

A function that executed when the focused row changes. Applies only to data rows. focusedRowEnabled should be true.

onFocusedRowChanging

A function that is executed before the focused row changes. Applies only to data rows. focusedRowEnabled should be true.

onInitialized

A function used in JavaScript frameworks to save the UI component instance.

onInitNewRow

A function that is executed before a new row is added to the UI component.

onKeyDown

A function that is executed when the UI component is in focus and a key has been pressed down.

onNodesInitialized

A function that is executed after the loaded nodes are initialized.

onOptionChanged

A function that is executed after a UI component property is changed.

onRowClick

A function that is executed when a grid row is clicked or tapped.

onRowCollapsed

A function that is executed after a row is collapsed.

onRowCollapsing

A function that is executed before a row is collapsed.

onRowDblClick

A function that is executed when a row is double-clicked or double-tapped. Executed after onCellDblClick.

onRowExpanded

A function that is executed after a row is expanded.

onRowExpanding

A function that is executed before a row is expanded.

onRowInserted

A function that is executed after a new row has been inserted into the data source.

onRowInserting

A function that is executed before a new row is inserted into the data source.

onRowPrepared

A function that is executed after a row is created.

onRowRemoved

A function that is executed after a row has been removed from the data source.

onRowRemoving

A function that is executed before a row is removed from the data source.

onRowUpdated

A function that is executed after a row has been updated in the data source.

onRowUpdating

A function that is executed before a row is updated in the data source.

onRowValidating

A function that is executed after cells in a row are validated against validation rules.

onSaved

A function that is executed after row changes are saved.

onSaving

A function that is executed before pending row changes are saved.

onSelectionChanged

A function that is executed after selecting a row or clearing its selection.

onToolbarPreparing

A function that is executed before the toolbar is created.

pager

Configures the pager.

paging

An object that configures paging.

parentIdExpr

Specifies which data field provides parent keys.

remoteOperations

Notifies the TreeList of the server's data processing operations. Applies only if data has a plain structure.

renderAsync

Specifies whether to render the filter row, command columns, and columns with showEditorAlways set to true after other elements.

repaintChangesOnly

Specifies whether to repaint only those cells whose data changed.

rootValue

Specifies the root node's identifier. Applies if dataStructure is "plain".

rowAlternationEnabled

Specifies whether rows should be shaded differently.

rowDragging

Configures row reordering using drag and drop gestures.

rtlEnabled

Switches the UI component to a right-to-left representation.

scrolling

Configures scrolling.

searchPanel

Configures the search panel.

selectedRowKeys

Allows you to select rows or determine which rows are selected.

selection

Configures runtime selection.

showBorders

Specifies whether the outer borders of the UI component are visible.

showColumnHeaders

Specifies whether column headers are visible.

showColumnLines

Specifies whether vertical lines that separate one column from another are visible.

showRowLines

Specifies whether horizontal lines that separate one row from another are visible.

sorting

Configures runtime sorting.

stateStoring

Configures state storing.

syncLookupFilterValues

Specifies whether to show only relevant values in the header filter and filter row.

tabIndex

Specifies the number of the element when the Tab key is used for navigating.

toolbar

Configures the toolbar.

twoWayBindingEnabled

Specifies whether to enable two-way data binding.

visible

Specifies whether the UI component is visible.

width

Specifies the UI component's width.

wordWrapEnabled

Specifies whether text that does not fit into a column should be wrapped.

Methods

This section describes methods that you can use to manipulate the TreeList UI component in code.

Name Description
addColumn(columnOptions)

Adds a new column.

addRow()

Adds an empty data row to the highest hierarchical level and switches it to the editing state.

addRow(parentId)

Adds an empty data row to a specified parent row.

beginCustomLoading(messageText)

Shows the load panel.

beginUpdate()

Postpones rendering that can negatively affect performance until the endUpdate() method is called.

byKey(key)

Gets a data object with a specific key.

cancelEditData()

Discards changes that a user made to data.

cellValue(rowIndex, dataField)

Gets the value of a cell with a specific row index and a data field, column caption or name.

cellValue(rowIndex, dataField, value)

Sets a new value to a cell with a specific row index and a data field, column caption or name.

cellValue(rowIndex, visibleColumnIndex)

Gets the value of a cell with specific row and column indexes.

cellValue(rowIndex, visibleColumnIndex, value)

Sets a new value to a cell with specific row and column indexes.

clearFilter()

Clears all filters applied to UI component rows.

clearFilter(filterName)

Clears all row filters of a specific type.

clearSelection()

Clears selection of all rows on all pages.

clearSorting()

Clears sorting settings of all columns at once.

closeEditCell()

Switches the cell being edited back to the normal state. Takes effect only if editing.mode is batch or cell and showEditorAlways is false.

collapseAdaptiveDetailRow()

Collapses the currently expanded adaptive detail row (if there is one).

collapseRow(key)

Collapses a row with a specific key.

columnCount()

Gets the data column count. Includes visible and hidden columns, excludes command columns.

columnOption(id)

Gets all properties of a column with a specific identifier.

columnOption(id, optionName)

Gets the value of a single column property.

columnOption(id, optionName, optionValue)

Updates the value of a single column property.

columnOption(id, options)

Updates the values of several column properties.

defaultOptions(rule)

Specifies the device-dependent default configuration properties for this component.

deleteColumn(id)

Removes a column.

deleteRow(rowIndex)

Removes a row with a specific index.

deselectAll()

Clears the selection of all rows on all pages or the currently rendered page only.

deselectRows(keys)

Cancels the selection of rows with specific keys.

dispose()

Disposes of all the resources allocated to the TreeList instance.

editCell(rowIndex, dataField)

Switches a cell with a specific row index and a data field to the editing state. Takes effect only if the editing mode is "batch" or "cell".

editCell(rowIndex, visibleColumnIndex)

Switches a cell with specific row and column indexes to the editing state. Takes effect only if the editing mode is "batch" or "cell".

editRow(rowIndex)

Switches a row with a specific index to the editing state. Takes effect only if the editing mode is "row", "popup" or "form".

element()

Gets the root UI component element.

endCustomLoading()

Hides the load panel.

endUpdate()

Refreshes the UI component after a call of the beginUpdate() method.

expandAdaptiveDetailRow(key)

Expands an adaptive detail row.

expandRow(key)

Expands a row with a specific key.

filter()

Gets a filter expression applied to the UI component's data source using the filter(filterExpr) method and the DataSource's filter property.

filter(filterExpr)

Applies a filter to the dataSource.

focus()

Sets focus on the UI component.

focus(element)

Sets focus on a specific cell.

forEachNode(callback)

Performs a pre-order tree traversal, executing a function on each visited node. Starts traversing from the top level nodes.

forEachNode(nodes, callback)

Performs a pre-order tree traversal, executing a function on each visited node. Starts traversing from the specified nodes.

getCellElement(rowIndex, dataField)

Gets a cell with a specific row index and a data field, column caption or name.

getCellElement(rowIndex, visibleColumnIndex)

Gets a cell with specific row and column indexes.

getCombinedFilter()

Gets the total filter that combines all the filters applied.

getCombinedFilter(returnDataField)

Gets the total filter that combines all the filters applied.

getDataSource()

Gets the DataSource instance.

getInstance(element)

Gets the instance of a UI component found using its DOM node.

getKeyByRowIndex(rowIndex)

Gets the key of a row with a specific index.

getNodeByKey(key)

Gets a node with a specific key.

getRootNode()

Gets the root node.

getRowElement(rowIndex)

Gets the container of a row with a specific index.

getRowIndexByKey(key)

Gets the index of a row with a specific key.

getScrollable()

Gets the instance of the UI component's scrollable part.

getSelectedRowKeys()

Gets the keys of the rows selected explicitly via the API or via a click or tap.

getSelectedRowKeys(mode)

Gets selected row keys.

getSelectedRowsData()

Gets the data objects of the rows selected explicitly via the API or via a click or tap.

getSelectedRowsData(mode)

Gets selected row data objects.

getVisibleColumnIndex(id)

Gets the index of a visible column.

getVisibleColumns()

Gets all visible columns.

getVisibleColumns(headerLevel)

Gets all visible columns at a specific hierarchical level of column headers. Use it to access banded columns.

getVisibleRows()

Gets currently rendered rows.

hasEditData()

Checks whether the UI component has unsaved changes.

hideColumnChooser()

Hides the column chooser.

instance()

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

isAdaptiveDetailRowExpanded(key)

Checks whether an adaptive detail row is expanded or collapsed.

isRowExpanded(key)

Checks whether a row is expanded or collapsed.

isRowFocused(key)

Checks whether a row with a specific key is focused.

isRowSelected(key)

Checks whether a row with a specific key is selected.

keyOf(obj)

Gets a data object's key.

loadDescendants()

Loads all root node descendants (all data items). Takes effect only if data has the plain structure and remoteOperations.filtering is true.

loadDescendants(keys)

Loads a specific node's descendants. Takes effect only if data has the plain structure and remoteOperations.filtering is true.

loadDescendants(keys, childrenOnly)

Loads all or only direct descendants of specific nodes. Takes effect only if data has the plain structure and remoteOperations.filtering is true.

navigateToRow(key)

Navigates to a row with the specified key.

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.

pageCount()

Gets the total page count.

pageIndex()

Gets the current page index.

pageIndex(newIndex)

Switches the UI component to a specific page using a zero-based index.

pageSize()

Gets the current page size.

pageSize(value)

Sets the page size.

refresh()

Reloads data and repaints data rows.

refresh(changesOnly)

Reloads data and repaints all or only updated data rows.

repaint()

Renders the component again without reloading data. Use the method to update the component's markup and appearance dynamically.

repaintRows(rowIndexes)

Repaints specific rows.

resetOption(optionName)

Resets a property to its default value.

saveEditData()

Saves changes that a user made to data.

searchByText(text)

Seeks a search string in the columns whose allowSearch property is true.

selectAll()

Selects all rows.

selectRows(keys, preserve)

Selects rows with specific keys.

selectRowsByIndexes(indexes)

Selects rows with specific indexes.

showColumnChooser()

Shows the column chooser.

state()

Gets the current UI component state.

state(state)

Sets the UI component state.

undeleteRow(rowIndex)

Recovers a row deleted in batch editing mode.

updateDimensions()

Updates the UI component's content after resizing.

See Also

Events

This section describes events raised by this UI component.

Name Description
adaptiveDetailRowPreparing

Raised before an adaptive detail row is rendered.

cellClick

Raised when a cell is clicked or tapped.

cellDblClick

Raised when a cell is double-clicked or double-tapped.

cellHoverChanged

Raised when the pointer enters or leaves a cell.

cellPrepared

Raised after a cell is created.

contentReady

Raised when the UI component is rendered and each time the component is repainted.

contextMenuPreparing

Raised before the context menu is rendered.

dataErrorOccurred

Raised when an error occurs in the data source.

disposing

Raised before the UI component is disposed of.

editCanceled

Raised after row changes are discarded.

editCanceling

Raised when the edit operation is canceled, but row changes are not yet discarded.

editingStart

Raised before a cell or row switches to the editing state.

editorPrepared

Raised after an editor is created.

editorPreparing

Raised before an editor is created.

focusedCellChanged

Raised after the focused cell changes.

focusedCellChanging

Raised before the focused cell changes.

focusedRowChanged

Raised after the focused row changes. Applies only when focusedRowEnabled is true.

focusedRowChanging

Raised before the focused row changes. Applies only when focusedRowEnabled is true.

initialized

Raised only once, after the UI component is initialized.

initNewRow

Raised before a new row is added to the UI component.

keyDown

Raised when the UI component is in focus and a key has been pressed down.

nodesInitialized

Raised after the loaded nodes are initialized.

optionChanged

Raised after a UI component property is changed.

rowClick

Raised when a row is clicked or tapped.

rowCollapsed

Raised after a row is collapsed.

rowCollapsing

Raised before a row is collapsed.

rowDblClick

Raised when a row is double-clicked or double-tapped.

rowExpanded

Raised after a row is expanded.

rowExpanding

Raised before a row is expanded.

rowInserted

Raised after a new row has been inserted into the data source.

rowInserting

Raised before a new row is inserted into the data source.

rowPrepared

Raised after a row is created.

rowRemoved

Raised after a row has been removed from the data source.

rowRemoving

Raised before a row is removed from the data source.

rowUpdated

Raised after a row has been updated in the data source.

rowUpdating

Raised before a row is updated in the data source.

rowValidating

Raised after cells in a row are validated against validation rules.

saved

Raised after row changes are saved.

saving

Raised before pending row changes are saved.

selectionChanged

Raised after selecting a row or clearing its selection.

toolbarPreparing

Raised before the toolbar is created.

See Also

Node

A TreeList node's structure.

import { DxTreeListTypes } from "devextreme-angular/ui/tree-list"
Type: DxTreeListTypes.Node

You can access nodes using the getRootNode() method and within some event handlers, for example, onNodesInitialized.

Row

A grid row.

import { DxTreeListTypes } from "devextreme-angular/ui/tree-list"
Type: DxTreeListTypes.Row

A row is a visual representation of a node. You can access grid rows using the getVisibleRows() method and within some event handlers, for example, onCellClick, onCellPrepared, onEditorPreparing.

Types

Name Description
AdaptiveDetailRowPreparingEvent

The type of the adaptiveDetailRowPreparing event handler's argument.

CellClickEvent

The type of the cellClick event handler's argument.

CellDblClickEvent

The type of the cellDblClick event handler's argument.

CellHoverChangedEvent

The type of the cellHoverChanged event handler's argument.

CellPreparedEvent

The type of the cellPrepared event handler's argument.

ContentReadyEvent

The type of the contentReady event handler's argument.

ContextMenuPreparingEvent

The type of the contextMenuPreparing event handler's argument.

DataErrorOccurredEvent

The type of the dataErrorOccurred event handler's argument.

DisposingEvent

The type of the disposing event handler's argument.

EditCanceledEvent

The type of the editCanceled event handler's argument.

EditCancelingEvent

The type of the editCanceling event handler's argument.

Editing

Configures editing.

EditingStartEvent

The type of the editingStart event handler's argument.

EditingTexts

Contains properties that specify texts for editing-related UI elements.

EditorPreparedEvent

The type of the editorPrepared event handler's argument.

EditorPreparingEvent

The type of the editorPreparing event handler's argument.

FocusedCellChangedEvent

The type of the focusedCellChanged event handler's argument.

FocusedCellChangingEvent

The type of the focusedCellChanging event handler's argument.

FocusedRowChangedEvent

The type of the focusedRowChanged event handler's argument.

FocusedRowChangingEvent

The type of the focusedRowChanging event handler's argument.

InitializedEvent

The type of the initialized event handler's argument.

InitNewRowEvent

The type of the initNewRow event handler's argument.

KeyDownEvent

The type of the keyDown event handler's argument.

NodesInitializedEvent

The type of the nodesInitialized event handler's argument.

OptionChangedEvent

The type of the optionChanged event handler's argument.

Paging

An object that configures paging.

RowClickEvent

The type of the rowClick event handler's argument.

RowCollapsedEvent

The type of the rowCollapsed event handler's argument.

RowCollapsingEvent

The type of the rowCollapsing event handler's argument.

RowDblClickEvent

The type of the rowDblClick event handler's argument.

RowExpandedEvent

The type of the rowExpanded event handler's argument.

RowExpandingEvent

The type of the rowExpanding event handler's argument.

RowInsertedEvent

The type of the rowInserted event handler's argument.

RowInsertingEvent

The type of the rowInserting event handler's argument.

RowPreparedEvent

The type of the rowPrepared event handler's argument.

RowRemovedEvent

The type of the rowRemoved event handler's argument.

RowRemovingEvent

The type of the rowRemoving event handler's argument.

RowUpdatedEvent

The type of the rowUpdated event handler's argument.

RowUpdatingEvent

The type of the rowUpdating event handler's argument.

RowValidatingEvent

The type of the rowValidating event handler's argument.

SavedEvent

The type of the saved event handler's argument.

SavingEvent

The type of the saving event handler's argument.

Scrolling

Configures scrolling.

Selection

Configures runtime selection.

SelectionChangedEvent

The type of the selectionChanged event handler's argument.

ToolbarPreparingEvent

The type of the toolbarPreparing event handler's argument.

TreeListCommandColumnType

Specifies the command column that this object customizes.

TreeListFilterMode

Specifies the filter and search parameters.

TreeListPredefinedColumnButton

Specifies buttons in the edit column or create a custom command column.

TreeListPredefinedToolbarItem

Specifies buttons in the toolbar.