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TreeList Events

Displays data as a multi-column tree view. Can be used in either bound or unbound mode. See Tree List for more information.
Name Description
AfterCheckNode Occurs after a node’s check state has been changed by an end-user.
AfterCollapse Fires immediately after a node has been collapsed.
AfterDragNode Fires immediately after a drag-and-drop operation on a node has been successfully completed.
AfterDropNode Fires after a node is dropped.
AfterExpand Fires immediately after a node has been expanded.
AfterFocusNode Fires in response to focus being moved between nodes.
AutoSizeChanged This event is not relevant for this class. Inherited from Control.
BackColorChanged Occurs when the value of the BackColor property changes. Inherited from Control.
BackgroundImageChanged Occurs when the value of the BackgroundImage property changes. Inherited from Control.
BackgroundImageLayoutChanged Occurs when the BackgroundImageLayout property changes. Inherited from Control.
BandWidthChanged Occurs when the band’s width is changed.
BeforeCheckNode Occurs before a node’s check state is changed.
BeforeCollapse Fires before a node is collapsed.
BeforeDragNode Fires when an attempt to drag a node is performed.
BeforeDropNode Fires when a node is about to be dropped, and allows you to cancel the operation.
BeforeExpand Fires before a node is expanded. Allows you to implement dynamic node loading in unbound mode.
BeforeFocusNode Fires before a node is focused.
BeforeLoadLayout Occurs before a layout is restored from storage (a stream, xml file or the system registry).
BindingContextChanged Occurs when the value of the BindingContext property changes. Inherited from Control.
CalcNodeDragImageIndex Enables you to specify a custom image to be displayed in front of nodes when dragging.
CalcNodeHeight Allows you to assign custom node height.
CausesValidationChanged Occurs when the value of the CausesValidation property changes. Inherited from Control.
CellValueChanged Fires when a cell value is changed.
CellValueChanging Fires when a user is changing a cell value in an editor.
ChangeUICues Occurs when the focus or keyboard user interface (UI) cues change. Inherited from Control.
Click Occurs when the control is clicked. Inherited from Control.
ClientSizeChanged Occurs when the value of the ClientSize property changes. Inherited from Control.
ClipboardNodePasting Repeatedly fires for each pasted row before updating the control, and allows you to modify pasted data and cancel pasting the currently processed row.
ColumnButtonClick Fires when the column button is clicked.
ColumnChanged Fires immediately after the column collection or an individual column has been modified.
ColumnFilterChanged Occurs when a column’s filter condition is changed.
ColumnPositionChanged Fires when a column is moved, hidden, or shown.
ColumnUnboundExpressionChanged Fires after a column’s TreeListColumn.UnboundExpression property has been changed.
ColumnWidthChanged Fires after a column’s width has been changed.
CompareNodeValues Enables you to implement custom sorting for columns whose TreeListColumn.SortMode property is set to Custom. For versions 17.1 and higher, the CompareNodeValues event is deprecated and replaced with the TreeList.CustomColumnSort event.
ContextMenuChanged Occurs when the value of the ContextMenu property changes. Inherited from Control.
ContextMenuStripChanged Occurs when the value of the ContextMenuStrip property changes. Inherited from Control.
ControlAdded Occurs when a new control is added to the Control.ControlCollection. Inherited from Control.
ControlRemoved Occurs when a control is removed from the Control.ControlCollection. Inherited from Control.
CreateCustomNode Provides the ability to create custom nodes.
CursorChanged Occurs when the value of the Cursor property changes. Inherited from Control.
CustomColumnDisplayText Fires for both bound and unbound Tree List columns and allows you to provide a custom display text for any cell.
CustomColumnSort Allows you to apply custom sorting for those Tree List columns whose TreeListColumn.SortMode is set to Custom.
CustomDrawBandHeader Provides the capability to custom paint band headers.
CustomDrawColumnHeader Provides the ability to custom paint column headers and the column button.
CustomDrawEmptyArea Enables you to custom paint a Tree List’s empty area.
CustomDrawFilterPanel Enables you to custom paint the Filter Panel.
CustomDrawFooter Gives you the ability to perform custom painting of the summary footer.
CustomDrawFooterCell Gives you the ability to perform custom painting of column footer cells.
CustomDrawNodeButton Gives you the ability to perform custom painting of expand buttons.
CustomDrawNodeCell Provides the ability to perform custom painting of node cells.
CustomDrawNodeCheckBox Enables you to manually paint node check boxes.
CustomDrawNodeImages Provides the ability to perform custom painting of node state and select images.
CustomDrawNodeIndent Enables tree indents to be painted manually.
CustomDrawNodeIndicator Provides the ability to perform custom painting of indicator cells.
CustomDrawNodePreview Allows you to custom paint preview sections.
CustomDrawRow Provides the ability to perform custom painting of rows.
CustomDrawRowFooter Provides the ability to perform custom painting of row footers.
CustomDrawRowFooterCell Provides the ability to perform custom painting of row footer cells.
CustomDrawScroll Allows you to draw custom scrollbars, or highlight specific positions on the scrollbars.
CustomFilterDisplayText Allows the text displayed within the Filter Panel to be customized.
CustomizeNewNodeFromOuterData Fires when a node from another TreeList control is dropped onto the current TreeList control and thus, a new node in the current TreeList is about to be created. The event allows you to provide data for the new node that is to be created.
CustomNodeCellEdit Enables editors to be assigned to cells on an individual basis.
CustomNodeCellEditForEditing Allows you to assign a custom editor to a column for in-place editing and override the default column editor, which is by default used both in display and edit modes.
CustomRowFilter Allows you to specify the node visibility, regardless of the currently applied filter.
CustomScrollAnnotation Allows you to specify custom annotations.
CustomUnboundColumnData Allows you to provide data to unbound columns, and save their modified records to an external source.
DataSourceChanged Occurs whenever the TreeList changes its data source.
DefaultPaintHelperChanged Fires when a different paint helper is assigned to the TreeList control.
Disposed Occurs when the component is disposed by a call to the Dispose() method. Inherited from Component.
DockChanged Occurs when the value of the Dock property changes. Inherited from Control.
DoubleClick Occurs when the control is double-clicked. Inherited from Control.
DpiChangedAfterParent Occurs when the DPI setting for a control is changed programmatically after the DPI of its parent control or form has changed. Inherited from Control.
DpiChangedBeforeParent Occurs when the DPI setting for a control is changed programmatically before a DPI change event for its parent control or form has occurred. Inherited from Control.
DragCancelNode Fires immediately after a drag-and-drop operation over a node has been canceled.
DragDrop Occurs when a drag-and-drop operation is completed. Inherited from Control.
DragEnter Occurs when an object is dragged into the control’s bounds. Inherited from Control.
DragLeave Occurs when an object is dragged out of the control’s bounds. Inherited from Control.
DragObjectDrop Fires immediately after the drag and drop operation has been completed.
DragObjectOver Enables you to control whether the dragged column header can be dropped at the current position.
DragObjectStart Fires when an end-user attempts to drag a column header.
DragOver Occurs when an object is dragged over the control’s bounds. Inherited from Control.
EditorKeyDown Occurs when a key is pressed within an in-place editor that belongs to the container control. Inherited from EditorContainer.
EditorKeyPress Occurs when a character key is pressed within an in-place editor that belongs to the container control. Inherited from EditorContainer.
EditorKeyUp Occurs when a pressed key is released within an in-place editor that belongs to the container control. Inherited from EditorContainer.
EnabledChanged Occurs when the Enabled property value has changed. Inherited from Control.
EndSorting Fires after a sorting operation has finished.
Enter Occurs when the control is entered. Inherited from Control.
FilterEditorCreated Allows you to customize the Filter Editor before it is displayed on screen.
FilterNode This event is obsolete. Use the TreeList.CustomRowFilter event instead.
FilterPopupExcelCustomizeTemplate Allows you to customize templates used by Excel-style Filter Dropdowns and external editors generated using Filtering UI Context.
FilterPopupExcelData Allows you to remove and modify items in the Excel-style Filter Dropdown, as well as add your own custom items that apply specific filtering conditions.
FilterPopupExcelPrepareTemplate Allows you to replace templates used by Excel-style Filter Dropdowns and external editors generated using Filtering UI Context.
FilterPopupExcelQueryFilterCriteria Fires when a new data filter is about to be applied to the control using the Excel-style Filter Dropdown, and allows you to substitute the filter.
FocusedColumnChanged Fires immediately after focus has been moved from a column.
FocusedNodeChanged Fires immediately after changing the focused node.
FontChanged Occurs when the Font property value changes. Inherited from Control.
ForeColorChanged Occurs when the ForeColor property value changes. Inherited from Control.
FormatRuleExpressionEditorCreated Allows you to customize the Expression Editor embedded in the Edit Formatting Rule dialog.
GetCustomNodeCellEdit Obsolete. Provides the ability to assign editors to individual cells.
GetCustomNodeCellStyle Obsolete. Provides the ability to assign custom style to individual cells.
GetCustomSummaryValue Enables you to perform custom summary value calculations.
GetNodeDisplayValue Provides the ability to display custom values within cells.
GetPreviewText Enables you to supply custom text for nodes’ preview sections.
GetPrintCustomSummaryValue Permits manual calculations of summary values for the printed version of the Tree List control.
GetPrintPreviewText Enables you to display custom text in preview sections when the control is printed.
GetSelectImage Allows you to dynamically assign select images to nodes.
GetStateImage Allows you to assign state images to nodes.
GiveFeedback Occurs during a drag operation. Inherited from Control.
GotFocus Occurs when the control receives focus. Inherited from Control.
HandleCreated Occurs when a handle is created for the control. Inherited from Control.
HandleDestroyed Occurs when the control’s handle is in the process of being destroyed. Inherited from Control.
HelpRequested Occurs when the user requests help for a control. Inherited from Control.
HiddenEditor Fires immediately after a cell editor has been closed.
HideCustomizationForm Fires immediately after the Customization Form has been closed.
ImeModeChanged Occurs when the ImeMode property has changed. Inherited from Control.
Invalidated Occurs when a control’s display requires redrawing. Inherited from Control.
InvalidNodeException Fires when a node fails validation or when its data cannot be saved to the data source.
InvalidValueException Enables you to handle exceptions raised as a result of assigning invalid values to cells.
KeyDown Occurs when a key is pressed while the control has focus. Inherited from Control.
KeyPress Occurs when a character. space or backspace key is pressed while the control has focus. Inherited from Control.
KeyUp Occurs when a key is released while the control has focus. Inherited from Control.
Layout Occurs when a control should reposition its child controls. Inherited from Control.
LayoutUpdated Fires after a Tree List’s layout has been changed.
LayoutUpgrade Occurs after a layout the version of which doesn’t match the current layout version used has been loaded from storage (a stream, xml file or system registry).
Leave Occurs when the input focus leaves the control. Inherited from Control.
LeftCoordChanged Fires when the control’s content is scrolled horizontally.
Load Occurs when a TreeList control is displayed for the first time.
LocationChanged Occurs when the Location property value has changed. Inherited from Control.
LostFocus Occurs when the control loses focus. Inherited from Control.
MarginChanged Occurs when the control’s margin changes. Inherited from Control.
MeasurePreviewHeight Allows you to specify the height of individual preview sections in pixels.
MouseCaptureChanged Occurs when the control loses mouse capture. Inherited from Control.
MouseClick Occurs when the control is clicked by the mouse. Inherited from Control.
MouseDoubleClick Occurs when the control is double clicked by the mouse. Inherited from Control.
MouseDown Occurs when the mouse pointer is over the control and a mouse button is pressed. Inherited from Control.
MouseEnter Occurs when the mouse pointer enters the control. Inherited from Control.
MouseHover Occurs when the mouse pointer rests on the control. Inherited from Control.
MouseLeave Occurs when the mouse pointer leaves the control. Inherited from Control.
MouseMove Occurs when the mouse pointer is moved over the control. Inherited from Control.
MouseUp Occurs when the mouse pointer is over the control and a mouse button is released. Inherited from Control.
MouseWheel Occurs when the mouse wheel moves while the control has focus. Inherited from Control.
Move Occurs when the control is moved. Inherited from Control.
NodeCellStyle Allows you to customize the appearance of individual cells.
NodeChanged Fires after the node’s property has changed.
NodesReloaded Fires when the Tree List control reloads all nodes.
PaddingChanged Occurs when the control’s padding changes. Inherited from Control.
Paint Occurs when the control is redrawn. Inherited from Control.
PaintEx A DirectX-compatible method that replaces the standard Control.Paint method.
ParentChanged Occurs when the Parent property value changes. Inherited from Control.
ParseFindPanelText Fires after the query in the find panel changes. Allows you to create a filter condition based on the query and specify how to highlight results in the control.
PopupMenuShowing Allows you to customize the default menus for column headers, summary footers and nodes.
PreviewKeyDown Occurs before the KeyDown event when a key is pressed while focus is on this control. Inherited from Control.
PrintExportProgress Fires repeatedly while the TreeList’s data is being printed/exported.
QueryAccessibilityHelp Occurs when AccessibleObject is providing help to accessibility applications. Inherited from Control.
QueryContinueDrag Occurs during a drag-and-drop operation and enables the drag source to determine whether the drag-and-drop operation should be canceled. Inherited from Control.
QueryCustomFunctions Allows you to add custom function based filters (for example, ‘discount is more than 15%’) to Excel-style pop-up filter menus and/or the filter editor.
RegionChanged Occurs when the value of the Region property changes. Inherited from Control.
Resize Occurs when the control is resized. Inherited from Control.
RightToLeftChanged Occurs when the RightToLeft property value changes. Inherited from Control.
RowCellClick Fires when a cell is clicked.
RowClick Fires when a row (node) is clicked.
RowSelectImageClick Fires when a row’s select image is clicked.
RowStateImageClick Fires when a row’s state image is clicked.
ScrollAnnotationsStyle Allows you to customize the scrollbar annotation color and alignment.
SelectImageClick Fires when the user clicks a node’s select image.
SelectionChanged Fires in response to changing selection when the TreeList is in multiselect mode.
ShowCustomizationForm Fires immediately after the Customization Form has been displayed.
ShowFilterPopupCheckedListBox Allows you to customize checked Column’s Filter DropDown lists before they are displayed.
ShowFilterPopupDate Allows you to customize a column’s dropdown calendar before it is displayed.
ShowFilterPopupExcel Allows you to hide specific filtering conditions from the “Filters” tab of the Excel-style Filter Dropdown.
ShowFilterPopupListBox Enables you to customize a particular Column’s Filter DropDown.
ShowingEditor Fires before the TreeList is switched to edit mode.
ShownEditor Fires immediately after a cell editor has been invoked.
ShowTreeListMenu Obsolete. Allows you to customize the default menus for column headers, summary footers and nodes.
SizeChanged Occurs when the Size property value changes. Inherited from Control.
StartSorting Fires before a sorting operation is started.
StateChanged Fires after the Tree List’s state has changed.
StateImageClick Fires when the user clicks a node’s state image.
StyleChanged Occurs when the control style changes. Inherited from Control.
SubstituteFilter Allows you to replace the applied filter with another filter.
SystemColorsChanged Occurs when the system colors change. Inherited from Control.
TabIndexChanged Occurs when the TabIndex property value changes. Inherited from Control.
TabStopChanged Occurs when the TabStop property value changes. Inherited from Control.
TextChanged Occurs when the Text property value changes. Inherited from Control.
TopVisibleNodeIndexChanged Fires when the control’s content is scrolled vertically.
TreeListMenuItemClick Provides the ability to perform custom handling of a context menu item click.
UnboundExpressionEditorCreated Fires after an Expression Editor has been created for an unbound column.
Validated Occurs when the control is finished validating. Inherited from Control.
ValidateNode Gives you the ability to specify whether a modified node’s data is valid, and if this node can lose focus.
Validating Occurs when the control is validating. Inherited from Control.
ValidatingEditor Fires when an editor is validated.
VirtualTreeGetCellValue This event allows you to initialize cells (and optionally the check state) of the processed node, when populating the Tree List control with data dynamically.
VirtualTreeGetChildNodes This event allows you to provide root and child nodes, when populating the Tree List control with data dynamically.
VirtualTreeSetCellValue Allows changes that are made to node cells and check state to be stored.
VisibleChanged Occurs when the Visible property value changes. Inherited from Control.
See Also