Creating Views › Assign View Characteristics › Used as Both Input and Output

Used as Both Input and Output

The Used as Both Input and Output option allows import entity views to be exported and export entity views to be imported. Import views that are to be used for both input and output are labeled exported on the Action Diagram view list. Import views that are to be used for input only are labeled import only. Export views that are to be used for both input and output are marked imported; export views that are to be used for export only are labeled export only.

This characteristic cannot be set on the import and export view sets of Procedure Steps; it can be used only in action blocks.

Using a view as both input and output lets a single view act as both import and export views. This facilitates transaction restart or availability of information on a return from a link.

The following possibilities can occur when import views are used as both input and output:

• SET and MOVE may be used to change data.
• The import view can be changed and the changes can be returned to the calling action block.
• Import views used for export do not need to be moved to export at the start of each Action Diagram.

Import views that are not used for both input and output may not be matched to views that are used for both input and output; the calling view cannot be changed on return from the called action block.

For export views, the view is not initialized on entry to the action block. The export view may also receive data into action blocks. When export views are selected for import, any values in the view of the calling action block pass to the called action block.

Downstream Effects: Import views selected to be used as both input and output are updated in the called action block. The calling action block also sees the results. For export views selected to be used as both input and output, the called action block sees data passed from the calling action block.

Using a view as both input and output allows values to be returned to entity views using call by reference instead of call by value.