Use Watchers mode to add Watchers to a Screen. During a Request or while previewing the Screen, a Watcher monitors when the value of a control in that Screen changes or receives a value, acts upon a Data Connector or runs a Script using that control's value, and then outputs its result to another Screen control.
A Watcher does the following, in this order during an in-progress Request or while previewing a Screen:
The Watcher monitors when the value of a control in that Screen changes or receives a value. This control is designated by its Variable Value setting, which becomes a Request variable when this Screen is used in a Request.
The Watcher performs an action against a designated Data Connector or Script as configured in that Watcher:
Data Connector: The Watcher acts upon a resource to access that Data Connector. The resources in this Data Connector may reference API endpoints, Collection records, or other data source resources.
Script: The Watcher runs the Script using the input data and Script configuration.
After the Watcher performs its action, it outputs its result to a designated Screen control. This control is designated by its Variable Value setting (the Request variable). This Request variable may be in that Screen or another that is used during that Request. If outputting its result to a Request variable not in that Screen, the Watcher's result becomes part of the Request's data during an in-progress Request; if this Request variable matches that of a control during that Request, that Watcher's output value overwrites the target control's existing value. Note that previewing a Watcher when it outputs its result to a Request variable not on that Screen is not possible since a preview only applies to that Screen.