You must have completed the required steps in Defining and Using a Basic Type .
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1. Call the ALE development menu. Choose SAP menu ® Tools ® IDoc Interface/ALE ® Development ® Inbound Processing ® Function Module ® Maintain Attributes (BD51).
2. Maintain the attributes for the function module and save your entries. Include the new entries in your transport request.
For an individual input, configure the attribute Input type depending on whether or not the called transaction locks the IDocs and updates the IDoc-Status. For more information on “ALE-capable transactions“ see Using Call Transaction.
In the example, enter 2 as the input type (Individual input with IDoc lock in transaction) and select the option “Dialog possible” (the function module should be able to call a dialog transaction).