Lookup Lists

A single lookup-list object (selection list) will often get used by multiple views. A vendor entry view and a check entry view will both use the same vendor list. Therefore, it does not make sense to encapsulate such a list inside a view (it should be accessible to all views). Normally, a file’s DataDictionary subclass will specify what lookup list should be assigned to which field. When this field is used in a DEO, it will automatically attempt to use the lookup list assigned to it in its file’s data dictionary. Because of this, lookup lists tend to be assigned in the data-dictionary subclass (with a use command) and not directly in the view.

Lookup List components are based on the dbModalPanel class and usually contain a DDO structure, a dbList object (that is connected to the DDO structure) and several Button objects. The same rules for creating and connecting DDOs used with Views can be applied to Lookup Lists.

Lookup Lists components have a file extension of “.sl”.

The DataFlex sample workspaces all contain examples of Lookup List objects.

 

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