Carousel (Prim_Caro)
DirectX Only
Carousel is a member of a group of list related primitive controls referred to as User Designed Controls.
Carousel organises individual design panels, typically images, in to linear or elliptical sequence with only one central design panel being fully visible
UDCs can be manipulated by the use of the typical LANSA list commands ADD_ENTRY, UPD_ENTRY etc. When entries are added to the list, an instance of the design is made, fields can be passed in, and a corresponding list item is made. UDCs control the position of the item within the list, manage selection, focus, expand/collapse etc., and communicate with the individual item designs through a series of predefined methods published on an interface specific to the type of UDC. For Prim_Caro this is #Prim_Caro.iCarouselDesign
All UDCs use a parameterized type to define the class of the design to be created each time an entry is added. This is specified on the DEFINE_COM as below
Define_Com Class(#Prim_Caro<#MyCarouselDesign>) Name(#Carousel)
Because of the overhead of making a reusable part instance compared to a simple item for a tree view (#Prim_TRVW) or list view (#Prim_LTVW), UDCs are not designed to be used with many thousand items. For high volume scenarios, other techniques are recommended.