Module org.omnifaces
Package org.omnifaces.component.input

Class ViewAction

  • All Implemented Interfaces:
    ActionSource, ActionSource2, PartialStateHolder, StateHolder, TransientStateHolder, ComponentSystemEventListener, FacesListener, SystemEventListenerHolder, EventListener
    public class ViewAction
extends UIViewAction

    The <o:viewAction> is a component that extends the standard <f:viewAction> and changes the if attribute to be evaluated during INVOKE_APPLICATION phase instead of the APPLY_REQUEST_VALUES phase. This allows developers to let the if attribute check the converted and validated model values before performing the view action, which results in much more intuitive behavior.

    In below example, the FooConverter may convert a non-null parameter to null without causing a validation or conversion error, and the intent is to redirect the current page to otherpage.xhtml when the converted result is null. 

     <f:viewParam name="foo" value="#{bean.foo}" converter="fooConverter" />
 <f:viewAction action="otherpage" if="#{bean.foo eq null}" />

    This is however not possible with standard <f:viewAction> as it evaluates the if attribute already before the conversion has taken place. This component solves that by postponing the evaluation of the if attribute to the INVOKE_APPLICATION phase. 

     <f:viewParam name="foo" value="#{bean.foo}" converter="fooConverter" />
 <o:viewAction action="otherpage" if="#{bean.foo eq null}" />

    Only when you set immediate="true", then it will behave the same as the standard <f:viewAction>.

    Usage

    You can use it the same way as <f:viewAction>, you only need to change f: to o:. 

     <o:viewAction action="otherpage" if="#{bean.property eq null}" />

    Messaging

    You can use the message attribute to add a global flash warning message. 

     <o:viewAction ... message="Please use a valid link from within the site" />

    Note that the message will only be shown when the redirect has actually taken place. The support was added in OmniFaces 3.2.

    Since:
    2.2
    Author:
    Bauke Scholtz

    • Field Detail

      • COMPONENT_TYPE

        public static final String COMPONENT_TYPE
        The component type, which is "org.omnifaces.component.input.ViewAction".
        See Also:
        Constant Field Values

    • Constructor Detail

      • ViewAction

        public ViewAction()

    • Method Detail

      • isRendered

        public boolean isRendered()
        Returns true if the immediate="true" attribute is not set, otherwise delegate to super, hereby maintaining the original behavior of immediate="true".
        Overrides:
        isRendered in class UIViewAction

      • getMessage

        public String getMessage()
        Returns the global flash warning message to be shown in the redirected page.
        Returns:
        The global flash warning message to be shown in the redirected page.
        Since:
        3.2

      • setMessage

        public void setMessage​(String message)
        Sets the global flash warning message to be shown in the redirected page.
        Parameters:
        message - The global flash warning message to be shown in the redirected page.
        Since:
        3.2