The hot item is defined as the currently selected item when hot tracking (and hover selection) is enabled.If hot tracking is enabled, when a user pauses over a list view item, the item label is automatically highlited without the use of a mouse button. The selection is the item index from which a multiple selection starts.
SetSelectionMark：设置List view 控件的选中标记.
SetHotItem一直处于高亮状态
SetSelectionMark你选中后他的颜色有所不同，当然颜色可以自己定义
The selection is the item index from which a multiple selection starts.