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WireHose Developers Guide
WHApplicationHelper is a class that handles application-level WireHose functionality. All its methods are static, so you never instantiate or subclass it. Its primary responsibilities are providing access to system properties, initializing WireHose data structures, providing access to the application's layout dictionary, and handling access control. During startup, the application helper also controls whether and how WireHose will modify EOModels by automatically creating subentities for particular entities.See "Multiple affiliates and auto subentities" for more information about this feature.
In response to WOApplication's
ApplicationWillFinishLaunching notification, the
application helper performs a number of initialization tasks. These
include getting system properties, setting default values, and
logging the values of WireHose-specific properties.
Once it has completed initialization, WHApplicationHelper posts an
ApplicationHelperDidFinishInitializing notification to
declare that it's now safe to access WireHose objects. This is the
notification Hello World's Application.java listens for before
importing and crawling feeds.
WHApplicationHelper provides a delegate interface so you can customize its behavior. It defines several methods which you can use to customize how users are logged in, how guest users get created, and whether or not a user can view, edit or delete objects.
Typically you'll set your application class as WHApplicationHelper's delegate, but any object can be a delegate. You don't need to implement all the methods in the interface or declare that your object implements the interface; WHApplicationHelper will only call the delegate methods you implement.
You can override how WireHose associates a user with a session by
implementing a delegate method called
You can inspect whatever formvalues, cookies or headers you find in
the request to determine the user to return. You can also control how
guest users are created or fetched through the
The various WireHose layout components, pages and direct actions
will query WHApplicationHelper to determine if a user is allowed to
view, edit or delete objects. You can implement the
userCanDeleteObject delegate methods to override the
default behavior. The
also available so you can quickly filter entire arrays rather than
single objects. Note that these methods will be called often, so they
should have as little overhead as possible.
Copyright ©2000-2003 Gary Teter. All rights reserved. WireHose is a trademark of Gary Teter.