When a view wrapper creates its view, it initializes the attribute-to-attribute connections in the parent part. In VisualAge Smalltalk V3.0, this initialization forces the view wrapper to always be the target of the alignment whether or not it is the target of the connection, and also whether or not the connection is unidirectional. In VisualAge Smalltalk V4.0, this initialization changed to make it consistent with the initialization of any attribute-to-attribute connection. This means that if the target attribute is read-only or the source attribute's value is nil, and the connection is bidirectional (source attribute is not read-only and the target attribute's value is not nil), the source of the connection is aligned with the target; otherwise, the target of the connection is aligned with the source.

This change may cause changes in the behavior of your Version 3.0 applications. To minimize the cases where there is behavior change between VisualAge Smalltalk V3.0 and VisualAge Smalltalk V4.5, the current VA Smalltalk migration will reverse all connections involving a view wrapper where the view wrapper was a source. At the end of migration, all connections involving view wrappers will have the view wrappers as targets.

The following table summarizes the different cases with results in VisualAge Smalltalk V3.0 compared to results in the current version of VA Smalltalk, and the last column Need user attention indicates the cases you might want to look at after migration.