Message System

This section presents the message-based interface used to manipulate the Showcase application.

The primary method of customizing the behavior and appearance of Showcase is via a message broadcast system. This system allows Showcase to be controlled locally by Python scripts and embededded custom web user interfaces, or remotely by external custom web user interfaces.

There are three primary kinds of messsages:

• Action messages - these are messages sent to Showcase and its add-ins to request that it change its state in some way, to request information, or to perform some action.
• Response messages - these are messages sent from Showcase and its add-ins in response to an action message to provide pertinent information, such as whether a requested action failed.
• Information messages - these are messages sent from Showcase, an add-in, or a custom UI that indicate a change in state, or that some event has occured.

Many action messages are treated as requests and have accompanying response messages. An add-in or script will often wait for the appropriate response message in order to know if and when an action has succeeded or failed.