typedef void __fastcall (__closure *TMeasureItemEvent)(Vcl::Controls::TWinControl* Control, int Index, int &Height);
TMeasureItemEvent is the type for event handlers on custom-drawn controls that allow different items in a list to have different heights.
Control is a reference to the control that contains the item.
Index is the index of the item in the Items property.
The Height parameter is the height in pixels that the given item will occupy in the control. The Height parameter is passed by reference (a var parameter), which initially contains the default height of the item or the height of the item text in the control's font. The handler can set Height to a value appropriate to the contents of the item, such as the height of a graphical image to be displayed within the item.