FRM075 - Using a Working List
- In the event-driven program model, when the user selects multiple items in a list, each item is processed individually by a call to the event that is triggered.
- The SELECTLIST command is very similar to the SELECT command. It creates a loop structure to process multiple records from a list.
- The list operations also support the use of IF_STATUS commands.
- Working lists are created using a DEF_LIST command within the program code. The list definition includes the fields in the list and the size (maximum number of entries) of the list.
- The working list counter is updated automatically.
- The TRANSFORM_LIST BIF will produce a text file, with a number of formats options available, from a working list.
- Windows applications can be called using the SYSTEM_COMMAND BIF.
Tips & Techniques
- Allowing users to select multiple items from a list and then performing some action against the resulting selected list of items is a very common requirement in Windows applications.
- Most lists have a property that indicates whether multiple item selection is to be allowed or not. By default, multiple item selection is supported. You should always think about whether or not you want to support multiple item selection and set this property accordingly.
What You Should Know
- How to use lists with list views.
- How to locate, update and delete entries from a list.
- How to select items from a list using the SELECTLIST command.
- How to use the following list commands:
- How to use the TRANSFORM_LIST Built-in function.