org.apache.tapestry.services
Interface ComponentDefaultProvider

All Known Implementing Classes:

ComponentDefaultProviderImpl

public interface ComponentDefaultProvider

A service that can be injected into a component to provide common defaults for various types of parameters.

Method Summary

Binding	defaultBinding(String parameterName, ComponentResources resources) Checks to see if the container of the component (identified by its resources) contains a property matching the component's id.
String	defaultLabel(ComponentResources resources) Computes the default label for the component (which will generally be a Field).
Translator	defaultTranslator(String parameterName, ComponentResources resources) Provides a translator based on the bound parameter type, if possible.
ValueEncoder	defaultValueEncoder(String parameterName, ComponentResources resources) Gets or creates a value encoder based on the type of the named parameter.

Method Detail

defaultLabel

String defaultLabel(ComponentResources resources)

Computes the default label for the component (which will generally be a Field).

Parameters:

resources -

Returns:

the label, either extracted from the component's container's message catalog, or derived from the component's ComponentResourcesCommon.getId().

defaultBinding

Binding defaultBinding(String parameterName,
                       ComponentResources resources)

Checks to see if the container of the component (identified by its resources) contains a property matching the component's id. If so, a binding for that property is returned. This is usually the default for a Field's value parameter (or equivalent).

Parameters:

parameterName - the name of the parameter

resources - the resources of the component for which a binding is needed

Returns:

the binding, or null if the container does not have a matching property

defaultValueEncoder

ValueEncoder defaultValueEncoder(String parameterName,
                                 ComponentResources resources)

Gets or creates a value encoder based on the type of the named parameter. ValueEncoders are cached based on type.

Parameters:

parameterName - the name of the parameter whose type is used to locate a ValueEncoderFactory

resources - the resources of the component, from which parameter and its type are extracted

Returns:

the value encoder, or null if the type of the parameter is not known

defaultTranslator

Translator defaultTranslator(String parameterName,
                             ComponentResources resources)

Provides a translator based on the bound parameter type, if possible.

Parameters:

parameterName -

resources -

Returns:

the translator, or null