bug in multi-selection

I can reproduce this in vw7.6 and vw7.9 (on Win XP):

 

1) Starting with visual.im, load:

    $(VISUALWORKS)\examples\RefreshSelectionList.pcl

 

2) doIt:

    RefreshMultiSelectListExample open

 

3) In the left pane, scroll down and select the bottom item.

 

4) Right-click->'remove' the selection (bottom-most item).

 

5) Holding the shift key, click on some other item to make a selection.

 

6) Right-click->'remove' the selection yields

    UHE: Subscript out of bounds:

 

The index of the first removed item(s) is not removed from the MultiSelectionInList's ('removeSelect' ivar) selectionIndexHolder when the item is removed. The steps to reproduce differ slightly for our datasets in that the error happens after step 5 rather than step 6, but I did not find or write a dataset example in the plain visual.im.

 

True, it is not expected to hold the shift key to make a multi-selection if no items are currently selected, but we cannot control user actions.

 

Attached is my proposed fix, written for VW 7.6.