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Summary

Tag Name: <tr:subform>
Java Class: org.apache.myfaces.trinidad.component.core.CoreSubform
Component Type: org.apache.myfaces.trinidad.CoreSubform
Naming Container: Yes. When referring to children of this component ("partialTriggers", findComponent(), etc.), you must prefix the child's ID with this component's ID and a colon (':').

The CoreSubform represents an independently submittable region of a page. The contents of a subform will only be validated (or otherwise processed) if a component inside of the subform is responsible for submitting the page or if the default attribute is set to true. This allows for comparatively fine-grained control of which components will be validated and pushed into the model without the compromises of using entirely separate form elements.

We strongly recommend the use of a single <tr:form> per page, and using <tr:subform> where you might otherwise be tempted to use multiple forms. Multiple forms require multiple copies of page state, and user edits in forms that aren't submitted are always lost. When a page using subforms is submitted, page state is only written once, and all user edits are preserved.

See the UIXSubform Javadoc for more details on how subforms work.

Code Example(s)

<tr:form>
  <tr:subform>... search region ... </tr:subform>
  <tr:subform default="true"> ... main content ... </tr:subform>
</tr:form>

Events

Type Phases Description
org.apache.myfaces.trinidad.event.AttributeChangeEvent Invoke Application,
Apply Request Values		 Event delivered to describe an attribute change. Attribute change events are not delivered for any programmatic change to a property. They are only delivered when a renderer changes a property without the application's specific request. An example of an attribute change event might include the width of a column that supported client-side resizing.

Attributes

Name Type Supports EL? Description
attributeChangeListener javax.el.MethodExpression Only EL a method reference to an attribute change listener. Attribute change events are not delivered for any programmatic change to a property. They are only delivered when a renderer changes a property without the application's specific request. An example of an attribute change events might include the width of a column that supported client-side resizing.
binding org.apache.myfaces.trinidad.component.core.CoreSubform Only EL an EL reference that will store the component instance on a bean. This can be used to give programmatic access to a component from a backing bean, or to move creation of the component to a backing bean.
default boolean No Default Value: false

whether the subform should assume it has been submitted. When set to "true", "submitted" will be considered true if no other subform has been submitted.
id String No the identifier for the component. Every component may be named by a component identifier that must conform to the following rules:
  • They must start with a letter (as defined by the Character.isLetter() method) or underscore ( _ ).
  • Subsequent characters must be letters (as defined by the Character.isLetter() method), digits as defined by the Character.isDigit() method, dashes ( - ), or underscores ( _ ). To minimize the size of responses generated by JavaServer Faces, it is recommended that component identifiers be as short as possible. If a component has been given an identifier, it must be unique in the namespace of the closest ancestor to that component that is a NamingContainer (if any).
rendered boolean Yes Default Value: true

whether the component is rendered. When set to false, no output will be delivered for this component (the component will not in any way be rendered, and cannot be made visible on the client). If you want to change a component's rendered attribute from false to true using PPR, set the partialTrigger attribute of its parent component so the parent refreshes and in turn will render this component.