This is useful e.g. for scripting languages which need to handle shadow objects for most of wxWidgets' classes and which store a handle to such a shadow class as client data in that class. This data can either be of type void - in which case the data container does not take care of freeing the data again or it is of type wxClientData or its derivatives. In that case the container (e.g. a control) will free the memory itself later. Note that you must not assign both void data and data derived from the wxClientData class to a container.
Some controls can hold various items and these controls can additionally hold client data for each item. This is the case for wxChoice, wxComboBox and wxListBox. wxTreeCtrl has a specialized class wxTreeItemData for each item in the tree.
If you want to add client data to your own classes, you may use the mix-in class wxClientDataContainer.
|Virtual destructor. |