[Overview][Constants][Types][Classes][Procedures and functions][Index] Reference for unit 'ComCtrls' (#lcl)

TCustomListView.OwnerData

Enables or disables owner data (virtual) mode for the list view control.

Declaration

Source position: comctrls.pp line 1663

public property TCustomListView.OwnerData : Boolean
  read FOwnerData
  write SetOwnerData
  default False;

Description

OwnerData is a Boolean property which enables or disables virtual mode for the list view control.

When set to True, the Items property does not contain the actual data displayed on the control. The display values are retrieved using the OnData, OnDataFind, and OnDataHint event handlers. Only the most recently accessed owner data item exists in the list view control. This allows the list view to be used to display a large number of items with a minimal amount of overhead.

Set the value for the Count property in Items to indicate the number of owner data items available to the list view control. Assign a routine to OnData to populate an individual list item (and sub-items if needed) from the source for the owner data.

When OwnerData is set to False, all values displayed on the list view control are maintained in the Items property.

OwnerData is one of the TListViewProperty values included in the TListViewProperties set type and exchanged with the widgetset class. The property value is read from and written to the TCustomTreeview widgetset class instance when its handle is valid. Changing the value for the property causes the widgetset class to be updated with the new value.

See also

TCustomListView.Items

  

Collection of list items displayed on the list view control.

TCustomListView.OnData

  

Event handler signalled to the value(s) for a list item when OwnerData (virtual mode) has been enabled.

TCustomListView.OnDataFind

  

Event handler signalled to locate list item data when OwnerData (virtual) mode is enabled.

TCustomListView.OnDataHint

  

The event handler is not signalled in the current LCL implementation.

TListItems.Count

  

The number of TListItem instances stored in the container.

TListViewProperties

  

Set type used to store values from the TListViewProperty enumeration.

TListViewProperty

  

Represents Boolean properties used in TCustomListView.