Hi Ravi
Can you check the link below this is the detail it provided
http://www.consolut.com/en/s/sap-ides-access/d/s/doc/H-BBP_SUS_CONDITION
Definition Documents that are processed by SUS, such as purchase orders, confirmations, or invoices, use a complex logic to add a button to the document or table toolbar.
Whether or not a button is enabled or disabled depends on the attribute values that were assigned by the corresponding view controller.
Use
Previously, the logic for this was implemented, that is, hard-coded, in the views.
Now, however, conditions and values that can be customized are used to describe this logic, which is interpreted by a condition processor. This condition processor uses a new central Customizing table (BBP_SUS_BTNDEF) that configures the UI buttons in the SUS documents.
Each table line corresponds to one button. It allows you to define conditions that determine when a button is displayed or enabled. Up to three conditions can be maintained for each button. Condition values have only string values that are not case sensitive. Typically, values are: