Some Significant Usage Points

• It is obvious and implicit that the structure of the avVisualList used in VF_UM040O and VF_UM044O could change from VLF version to version. You need to code and test for this contingency.

• The list is the visualization of an instance list. It is not the instance list itself.  If you change the way that an instance list has been visualized, you are not changing the instance list.

• Do not save list or column or item references in your code. This would probably cause resource leakage or other problems.

• Do not change list or list items selection or focus. Update the instance list instead.

• Do not change list column or list item visibility unless you are sure it will not interfere with built in features like: Quick Search, Column Hide / Show and Column Filtering.

• Do not change list items inside beginlistupdate/endlistupdate code blocks.    

• The list reference can be used if you are using your own snap-in instance list browser, (though in most cases there is no need to do this). In order to do so, your snap in instance list browser must use a #PRIM_LIST, AND in your snap in instance list browser you need to override mthroutine uGetVisualList to supply a reference to the list control it uses. For example, if it uses a PRIM_LIST called #MyList:

Mthroutine Name(uGetVisualList) Options(*REDEFINE)

#uList <= #MyList

Endroutine

• Use caution with your changes and test carefully how they interact with the rest of the Framework.

• VL list programming skills are assumed.