TCustomTreeView

type TCustomTreeView = class(TCustomControl)

protected

  FChangeTimer: TTimer;

FChangeTimer - local variable to act as timer for changes

  FEditor: TEdit;

protected

  class procedure WSRegisterClass; override;

WSRegisterClass - Register this Class for the current Widget Set

  class function GetControlClassDefaultSize; override;

protected

  procedure Added(); virtual;

  procedure EditorEditingDone(); virtual;

  procedure EditorKeyDown(); virtual;

  procedure BeginAutoDrag; override;

Start the AutoDrag process.

  procedure BeginEditing();

  function DoDragMsg(); override;

DoDragMsg generates system message to indicate object and position for dragging and returns Result of action

  function CanChange(); virtual;

CanChange - returns True if a given TreeNode can be changed

  function CanCollapse(); virtual;

CanCollapse returns True if a given TreeNode is able to be collapsed

  function CanEdit(); virtual;

CanEdit - returns True if a Given TreeNode is allowed to be edited

  function CanExpand(); virtual;

CanExpand - returns True if the specified TreeNode can be expanded

  function CreateNode; virtual;

CreateNode - creates a new node in a TreeView and returns its content

  function CustomDraw(); virtual;

CustomDraw - returns True if Custom Drawing is proceeding in the specified Rectangle

  function CustomDrawItem(); virtual;

CustomDrawItem - returns True if Custom Image drawing is proceeding at the specified TreeNode

  function GetDragImages; override;

Get the list of Images to be dragged - returned as a list

  function GetMaxLvl;

GetMaxLvl - returns the maximum level of branching of the tree structure

  function GetMaxScrollLeft;

GetMaxScrollLeft - returns maximal extent of scrolling to the left

  function GetMaxScrollTop;

GetMaxScrollTop - returns the maximal extent of scrolling upwards

  function GetNodeAtInternalY();

GetNodeAtInternalY - returns the node at the specified internal (ie relative) Y coordinate

  function GetNodeAtY();

GetNodeAtY - returns the node at the specified (absolute) Y coordinate

  function GetNodeDrawAreaHeight;

GetNodeDrawAreaHeight - returns the height for the area in which node is drawn

  function GetNodeDrawAreaWidth;

GetNodeDrawAreaWidth - returns the width for the area in which node is drawn

  function IsCustomDrawn();

IsCustomDrawn - returns True if the specified target node is custom drawn

  function IsNodeVisible();

IsNodeVisible - returns True if the specified node is visible

  function IsNodeHeightFullVisible();

IsNodeHeightFullVisible - returns True if the full height of the specified node is visible in the current view

  function IsInsertMarkVisible; virtual;

IsInsertMarkVisible - returns True if an Insert mark is visible

  procedure Change(); virtual;

Change - software emulation of the OnChange event

  procedure Collapse(); virtual;

Collapse - software emulation of the OnCollapsed event

  procedure CreateWnd; override;

CreateWnd - Creates the Window

  procedure Delete(); virtual;

Delete - remove the specified node from the tree structure (software emulation of the OnDeletion event)

  procedure DestroyWnd; override;

DestroyWnd - destroy the window for this control

  procedure DoEndDrag(); override;

Invokes the OnEndDrag handler

  function DoMouseWheel(); override;

DoMouseWheel - performs the action to deal with a movement of the mouse wheel; returns True if handled

  procedure DoPaint; virtual;

DoPaint - perform the actual painting

  procedure DoPaintNode(); virtual;

DoPaintNode - perform the actual painting of the specified node

  procedure DoStartDrag(); override;

Invokes the OnStartDrag handler

  procedure DragOver(); override;

Determines whether a drop is acceptable, using the OnDragOver handler.

  procedure EndEditing();

EndEditing - finish editing

  procedure EnsureNodeIsVisible();

EnsureNodeIsVisible - method to make sure specified node is visible

  procedure Expand(); virtual;

Expand the specified node

  procedure GetImageIndex(); virtual;

GetImageIndex - returns the index of the image associated with the specified node

  procedure GetSelectedIndex(); virtual;

GetSelectedIndex - returns the index of the selected node

  procedure InitializeWnd; override;

InitializeWnd - initialise the window for this control

  procedure KeyDown(); override;

KeyDown - emulate the action of pressing the specified key (makes OnKeyDown respond)

  procedure Loaded; override;

Loaded makes a number of checks, using client size if specified, and copying appropriate flags, fonts, text etc, makes list of child controls to notify them of any changes, then calls inherited Loaded

  procedure MouseDown(); override;

MouseDown - a procedure that allows the programmer to simulate a mouse button being down over the control, and initiates the same Action as that associated with the OnMouseDown event

  procedure MouseMove(); override;

MouseMove - a procedure that allows the programmer to simulate a mouse being moved over the control, and initiates the same Action as that associated with the OnMouseMove event

  procedure MouseUp(); override;

MouseUp - a procedure that allows the programmer to simulate a mouse button being Up over the control, and initiates the same Action as that associated with the OnMouseUp event

  procedure Notification(); override;

Notification - calls inherited Notification, then takes action depending on Operation

  procedure Paint; override;

The default paint handler for the class

  procedure SetDragMode(); override;

SetDragMode - specify the mode for dragging

  procedure SetOptions();

SetOptions - specifies the options for the TreeView

  procedure UpdateDefaultItemHeight; virtual;

UpdateDefaultItemHeight - brings the value of the default item height up-to-date

  procedure WndProc(); override;

WndProc - message handler for the procedure of this window

  procedure UpdateInsertMark(); virtual;

UpdateInsertMark - see if there is an insert mark at X,Y and put one in if necessary

  procedure DoSelectionChanged; virtual;

DoSelectionChanged - perform the code required for a change in selection

  procedure WMHScroll(); message;

WMHScroll - LCL Message for horizontal scroll

  procedure WMVScroll(); message;

WMVScroll - LCL Message for Vertical scroll

  procedure WMLButtonDown(); message;

Protected messages to system - when left mouse button is down

  procedure WMNotify(); message;

WMNotify - LCL Notify message

  procedure WMSetFocus(); message;

  procedure WMKillFocus(); message;

  procedure Resize; override;

Checks for changes and calls DoOnResize

  property AutoExpand: Boolean; [rw]

AutoExpand - if True, the tree structure is automatically expanded when a node is selected

  property BorderStyle;

  property HideSelection: Boolean; [rw]

HideSelection - if True, the selected part of the tree is to be hidden

  property HotTrack: Boolean; [rw]

HotTrack - the property whereby the item under the mouse pointer becomes emphasised

  property Images: TCustomImageList; [rw]

Images - the ImageList to be used in association with the list of TreeNodes

  property Indent: Integer; [rw]

Indent - the amount by which each successive level of branching is to be indented in the tree structure

  property Items: TTreeNodes; [rw]

Items - the collection of TreeNodes that comprise the TreeView

  property MultiSelect: Boolean; [rw]

  property OnAddition: TTVExpandedEvent; [rw]

  property OnAdvancedCustomDraw: TTVAdvancedCustomDrawEvent; [rw]

OnAdvancedCustomDraw - event handler for advanced custom drawing

  property OnAdvancedCustomDrawItem: TTVAdvancedCustomDrawItemEvent; [rw]

OnAdvancedCustomDrawItem - event handleer for advanced custom drawing item

  property OnChange: TTVChangedEvent; [rw]

OnChange - specialised event handler for a change in the TreeView

  property OnChanging: TTVChangingEvent; [rw]

OnChanging - specialised event handler while TreeView is being changed

  property OnCollapsed: TTVExpandedEvent; [rw]

OnCollapsed - specialised event handler when part of the tree is collapsed

  property OnCollapsing: TTVCollapsingEvent; [rw]

OnCollapsing - specialised event handler while part of the tree is being collapsed

  property OnCompare: TTVCompareEvent; [rw]

OnCompare - specialised event handler for comparisons within the TreeView

  property OnCreateNodeClass: TTVCreateNodeClassEvent; [rw]

  property OnCustomCreateItem: TTVCustomCreateNodeEvent; [rw]

OnCustomCreateItem - event handler for custom item creation

  property OnCustomDraw: TTVCustomDrawEvent; [rw]

OnCustomDraw - event handler for custom drawing

  property OnCustomDrawItem: TTVCustomDrawItemEvent; [rw]

OnCustomDrawItem - event handler for custom drawing item

  property OnDeletion: TTVExpandedEvent; [rw]

OnDeletion - specialised event handler for deletion of node(s) from the tree

  property OnEdited: TTVEditedEvent; [rw]

OnEdited - specialised event handler when the TreeView has been edited

  property OnEditing: TTVEditingEvent; [rw]

OnEditing - specialised event handler while a TreeView is being edited

  property OnEditingEnd: TTVEditingEndEvent; [rw]

  property OnExpanded: TTVExpandedEvent; [rw]

OnExpanded - specialised event handler when a TreeView has been expanded

  property OnExpanding: TTVExpandingEvent; [rw]

OnExpanding - specialised event handler while a TreeView is being expanded

  property OnGetImageIndex: TTVExpandedEvent; [rw]

OnGetImageIndex - event handler for finding the index of an image

  property OnGetSelectedIndex: TTVExpandedEvent; [rw]

OnGetSelectedIndex - event handler for finding index of selected item

  property OnSelectionChanged: TNotifyEvent; [rw]

OnSelectionChanged - event handler for a change in the selection

  property ReadOnly: Boolean; [rw]

ReadOnly - if True, the TreeView can only be observed, and not Written to or changed. Default False

  property RightClickSelect: Boolean; [rw]

RightClickSelect - if True, a Right Click selects an Item. Default False

  property RowSelect: Boolean; [rw]

RowSelect - if True, a row is selected

  property ScrolledLeft: Integer; [rw]

ScrolledLeft - the position of the tree when fully scrolled to the left

  property ScrolledTop: Integer; [rw]

ScrolledTop - th eposition of th etree when fully scrolled to the top

  property ShowButtons: Boolean; [rw]

ShowButtons - if True, buttons are displayed

  property ShowLines: Boolean; [rw]

ShowLines - show the connecting lines of the tree structure

  property ShowRoot: Boolean; [rw]

ShowRoot - if True, the root of the tree structure is displayed

  property ShowSeparators: Boolean; [rw]

ShowSeparators - if True, separators are shown between items

  property SortType: TSortType; [rw]

SortType - the way the items are to be sorted: None, by Data, by Text or Both

  property StateImages: TCustomImageList; [rw]

StateImages - the list of images to denote state of the tree (expanded, contracted etc)

  property ToolTips: Boolean; [rw]

ToolTips - if True (default), pop-up tool tips are to be shown

public

  constructor Create(); override;

Create - constructor for TCustomTreeView: calls inherited Create then sets defaults for style, size, etc

  destructor Destroy; override;

Destroy - destructor for TCustomTreeView: frees images, nodes and links, then calls inherited Destroy

  function AlphaSort;

If True, sort alphabetically

  procedure ConsistencyCheck;

ConsistencyCheck - check that indexes of treenodes match those of images etc

  function CustomSort();

CustomSort - if True, an external sorting method specified by SortProc is to be used

  function DefaultTreeViewSort();

DefaultTreeViewSort - returns result of string comparison between names of Node1 and Node2

  procedure EraseBackground(); override;

EraseBackground - remove all material from the background

  function GetHitTestInfoAt();

GetHitTestInfoAt - returns the result of a hit test at the point (X, Y)

  function GetNodeAt();

GetNodeAt - returns the TreeNode at position (X. Y)

  procedure GetInsertMarkAt();

GetInsertMarkAt - find if there is an insert mark at the specified coordinates

  procedure SetInsertMark();

SetInsertMark - place an Insert mark at the specified node in the tree

  procedure SetInsertMarkAt(); virtual;

SetInsertMarkAt - place an insert mark at the specified coordinates

  procedure Invalidate; override;

Render this control non-valid

  function IsEditing;

IsEditing - returns True if editing is in progress

  procedure BeginUpdate;

BeginUpdate - start the update of the display

  procedure EndUpdate;

EndUpdate finishes updating the display

  procedure FullCollapse;

FullCollapse - method to collapse the treeview fully, ie show just the root

  procedure FullExpand;

FullExpand - method to expand the treeview fully, and show all the branches

  procedure LoadFromFile();

LoadFromFile - load the data from the specified file

  procedure LoadFromStream();

LoadFromStream - load data from the specified stream

  procedure SaveToFile();

SaveToFile - saves the data to the specified file

  procedure SaveToStream();

SaveToStream - save the data to the specified stream

  procedure WriteDebugReport();

WriteDebugReport - used for debugging

  procedure LockSelectionChangeEvent;

LockSelectionChangeEvent - if the selection has changed, lock its status

  procedure UnlockSelectionChangeEvent;

UnlockSelectionChangeEvent - unlock a selection to allow it to be changed

  function GetFirstMultiSelected;

GetFirstMultiSelected - returns the first node from a multiple selection

  function GetLastMultiSelected;

  function SelectionVisible;

SelectionVisible - returns True if a selection is visible

  procedure MakeSelectionVisible;

MakeSelectionVisible - method for making a selection visible

  property BackgroundColor: TColor; [rw]

BackgroundColor for the treeview

  property BorderWidth;

Property to determine width of the window's border

  property BottomItem: TTreeNode; [rw]

BottomItem - the last item on the list

  property DefaultItemHeight: Integer; [rw]

DefaultItemHeight - default height for items on the list

  property DropTarget: TTreeNode; [rw]

DropTarget - the target node for dropping a dragged item

  property ExpandSignType: TTreeViewExpandSignType; [rw]

ExpandSignType - the symbols to denote whether a list is expanded or collapsed; default is plus or minus

  property InsertMarkNode: TTreeNode; [rw]

InsertMarkNode - place a marker on the specified node

  property InsertMarkType: TTreeViewInsertMarkType; [rw]

InsertMarkType - the type of marker to be inserted

  property KeepCollapsedNodes: Boolean; [rw]

KeepCollapsedNodes - if True, the collapsed nodes are to be retained

  property MultiSelectStyle: TMultiSelectStyle; [rw]

  property Options: TTreeViewOptions; [rw]

The set of Options for displaying the tree view

  property ScrollBars: TScrollStyle; [rw]

ScrollBars - the style of scroll bars for the treeview display

  property Selected: TTreeNode; [rw]

The Selected tree nodes

  property SelectionColor: TColor; [rw]

SelectionColor - the colour to be used for the selected nodes, to distinguish them from the others

  property SelectionCount: Cardinal; [r]

  property Selections: TTreeNode; [r]

  property SeparatorColor: TColor; [rw]

SeparatorColor - the colour to be used for separators

  property TopItem: TTreeNode; [rw]

TopItem - the first visible node of the tree

  property TreeLineColor: TColor; [rw]

TreeLineColor - the colour to be used for the lines showing the tree structure

  property TreeLinePenStyle: TPenStyle; [rw]

TreeLinePenStyle - the pen style for drawing lines on the tree

  property ExpandSignColor: TColor; [rw]

ExpandSignColor - the colour to be used for the expand/collapse symbols

published

  property TabStop;

Is the control in the sequence of controls accessed by successive presses of the Tab key?

end;

TCustomTreeView

TCustomTreeView - ancestor class for TTreeView

TCustomControl

TCustomControl - a base class for many window controls

TWinControl

TControl

TLCLComponent

TLCLComponent - base class for LCL components

TComponent,IUnknown,IInterfaceComponentReference

TPersistent

TObject