Package net.sf.mmm.client.ui.api.handler

Contains interfaces for handlers of the UI.

See: Description

Interface Summary

Interface	Description
UiEventObserver	This is the interface for an observer, that gets notified before and after one or multiple UiHandler(s) get invoked.
UiHandler	This is the marker interface for a handler of action(s) in the context of a user-interface (UI).

Package net.sf.mmm.client.ui.api.handler Description

Contains interfaces for handlers of the UI.

UI Handlers API

This package and it sub-packages contain UiHandler-interfaces defining action operations for events triggered from the UI (user interface). These are call-back interfaces that will be implemented with the custom behavior for the particular event.
ATTENTION:
Typically these interfaces are implemented by a controller or presenter following the MVC or MVP paradigm. However, this should only be done if it helps to increase code quality (e.g. for separation of concerns). In various cases there are recurring UI patterns in an application client that are best addressed directly by reusable view logic. E.g. if you want to have a edit button to switch your UI to the edit mode, you will not increase your code quality if this has to be implemented redundantly by every controller or presenter. In other words we do not believe in strict MVC or MVP. See the documentation of UiElement for further details. On the other hand we strongly recommend that handler operations that perform advanced business logic or even invoke remote services should only be implemented in the controller/presenter. See also UiHandlerObject.