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The Motor Loaner System sample application includes three examples of a Windows Layout Control for the Rental Agreements, Associates, and Manufacturers entity (see "About the Configurations Included in the Sample Application" of the Developer Guide for for more information).
This topic focuses on the Rental Agreements layout control, which disables fields that are not applicable depending on the rental agreement's status (for example, Check-in fields are disabled for vehicles that have not been checked out yet). The logic that prevents modification to fields based on record state is implemented in the Rental Agreements entity object but the layout control enforces this behavior visually at the user interface. The layout control also automatically sets a Rental Agreement's Starting Mileage when a user specifies a Vehicle (based on the selected Vehicle's Current Mileage).
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