Designing the Procedure Interaction › Flows › Executing a Command via a Flow

Executing a Command via a Flow

Most server procedures rely on the value in the command special attribute to direct their processing.

When a procedure is initiated from a window or dialog box, the user selects a push button, menu item, toolbar item, and so on, to influence procedure execution. The same kind of value is required when a procedure is initiated by a flow from another procedure.

A command value can be specified for each direction of a flow. When the destination procedure of the flow executes, its underlying procedure action diagram treats the command value exactly as if it were entered on a window or dialog box.

You can choose to send one of the following:

• A specific command value
• For a transfer flow, specify the command value that triggers the destination procedure.
• For a link flow, specify both the command value that triggers the destination procedure, and the command value that triggers the return to the source procedure.
• The current value of command (its value at the conclusion of the source procedure's execution)
• For client/server, you will most often send the command of current. This lets the server know what the client is trying to accomplish.
• In the case of a return from a link, the previous value of command (the value in the command field when the procedure that initiated the link finished executing)