TCheckListBox class

In unit CheckLst

TCheckListBox implements a list box with check boxes for its items.

Declaration

pascal

TCheckListBox = class(TCustomCheckListBox)

Inheritance

Description

TCheckListBox is a TCustomCheckListBox descendant which implements a scrollable list box which displays check boxes for each of its items.

Use the Items property to define the caption for entries that appear in the control. Each of the Items can have a state of checked or unchecked (or "grayed" when AllowGrayed is set). Use the properties and methods such as Toggle, CheckAll, Checked, ItemEnabled, and State to maintain the items in the control.

It provides the scrolling, selection, and drawing styles inherited from the ancestor class. It also includes the ability to render its items as a check box, and to respond to mouse or keyboard events when an item is toggled.

Use the event handlers in the class to perform actions needed when one or more items are clicked or change their state value. Use OnItemClick to process item changes individually.

TCheckListBox sets the visibility for properties defined in the ancestor class.

Properties

`Align`	published	Specifies the placement of the control on its Parent control.
`AllowGrayed`	published	Indicates if the item can use the "grayed" (or unselectable) check box state.
`Anchors`	published	The set of anchor definitions for this control.
`BidiMode`	published	Indicates whether text controls use in bi-directional reading.
`BorderSpacing`	published	Determines the inner and outer border spacing for this control.
`BorderStyle`	published	Indicates the border style displayed around the control.
`Color`	published	The background color for the control.
`Columns`	published	The number of visible columns displayed on the control.
`Constraints`	published	Contains the minimum and maximum Width and Height for the control.
`DragCursor`	published	The cursor shape shown during a drag operation.
`DragMode`	published	Determines how a drag operation is started for the control.
`ExtendedSelect`	published	True when a contiguous range of items can be selected using Shift+Click. The default value is True.
`Enabled`	published	Determines whether the control responds to mouse or keyboard input.
`Font`	published	The font to be used for text display in this control.
`HeaderBackgroundColor`	published	Color used to paint the background for Header items on the control.
`HeaderColor`	published	Color used for the text on a Header item.
`IntegralHeight`	published	Not implemented: shrink the Height of the widget, so that it only shows fully visible rows.
`Items`	published	The list of items defined for the control.
`ItemHeight`	published	The default height for an item displayed in the list.
`ItemIndex`	published	Ordinal position for the currently selected item, -1 if none.
`MultiSelect`	published	Allows selection of more than one item from the list.
`Options`	published	Contains options enabled for the list box control.
`ParentBidiMode`	published	Indicates whether the BiDiMode settings in the Parent control are used.
`ParentColor`	published	Use the Color from the Parent control, when enabled.
`ParentFont`	published	Indicates if the Font from the Parent control is used in the control.
`ParentShowHint`	published	If True, the value of ShowHint for the control will be the same as the one from the Parent. Default is True.
`PopupMenu`	published	A context-sensitive menu that pops up when the right mouse button is clicked over this control.
`ShowHint`	published	Enables Hint display for the control.
`Sorted`	published	Determines whether the list entries are sorted in alphanumeric order.
`Style`	published	Controls the appearance of items on the list box control and indicates whether the control uses "virtual mode".
`TabOrder`	published	Indicates the navigation order for the control when the user presses the Tab or Shift+Tab key.
`TabStop`	published	Allows the user to navigate to / from the control by pressing the Tab or Shift+Tab keys.
`TopIndex`	published	Index of the first visible (or top-most) item.
`Visible`	published	Allows the control, and all of its children, to be displayed or hidden.

Events

`OnChangeBounds`	published	Event handler signalled when the Bounds for the control have been changed.
`OnClick`	published	Notification handler for mouse clicks.
`OnClickCheck`	published	Event handler signalled when a check box in the control has been changed.
`OnContextPopup`	published	Invoked when a context-sensitive pop-up menu is requested.
`OnDblClick`	published	Event handler signalled when a mouse double click occurs in the control.
`OnDrawItem`	published	Handler for painting of a list item in owner-draw mode.
`OnDragDrop`	published	Event handler signalled when an object is dropped onto the control.
`OnDragOver`	published	Event handler signalled when a control is dragged over the control instance.
`OnEndDrag`	published	Event handler signalled for the end of a drag-drop operation.
`OnEnter`	published	Event handler signalled when the control receives focus.
`OnExit`	published	Event handler signalled when the control loses focus.
`OnItemClick`	published	Deprecated. Event handler signalled when the check box state for a specific item has been changed.
`OnKeyPress`	published	Event handler signalled for character data entered by the user.
`OnKeyDown`	published	Event handler signalled for key down keyboard events.
`OnKeyUp`	published	Event handler signalled when a key up event has occurred for the control.
`OnMeasureItem`	published	Handler invoked when the height for an item is needed.
`OnMouseDown`	published	Event handler signalled when a mouse down event is handled for the control.
`OnMouseEnter`	published	Event handler signalled when the mouse pointer has entered the control.
`OnMouseLeave`	published	Event handler signalled when the mouse pointer has left the control.
`OnMouseMove`	published	Event handler signalled when the mouse pointer is moved in the control.
`OnMouseUp`	published	Event handler signalled when a mouse up event is handled for the control.
`OnMouseWheel`	published	Event handler for mouse wheel turned.
`OnMouseWheelDown`	published	Event handler signalled for a downward movement of the mouse wheel.
`OnMouseWheelUp`	published	Event handler signalled for an upward movement of the mouse wheel.
`OnMouseWheelHorz`	published	Event handler signalled for a horizontal movement of the mouse wheel.
`OnMouseWheelLeft`	published	Event handler signalled for a leftward movement of the mouse wheel.
`OnMouseWheelRight`	published	Event handler signalled for a rightward movement of the mouse wheel.
`OnResize`	published	Notification handler for a resize of the control.
`OnSelectionChange`	published	Handler invoked when an item is selected in the control.
`OnShowHint`	published	Event handler signalled when a hint window is displayed for the control.
`OnStartDrag`	published	Event handler signalled for the start of a dragging operation.
`OnUTF8KeyPress`	published	Handler for a character entered by the user.