<document>
    <body>

        <section name="Examples">

            <p>
                The Delegate component allows us to be very flexible in how and what gets rendered, and
                in what order. In some cases, the object to be rendered may come from an entirely
                different page.
            </p>

            <p>
                This example is simpler, and could easily be accomplished using an If component. We'll create
                a page that can be used for viewing or editting an object.
            </p>

            <subsection name="ViewAccount.tml">

                <source><![CDATA[
<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_0_0.xsd">
    <body>
        <h1>View Account</h1>

        <t:delegate to="activeBlock"/>

        <t:block id="view">
            <t:beandisplay object="account"/>

            <p><t:actionlink t:id="edit">Edit this account</t:actionlink></p>
        </t:block>

        <t:block id="edit">
            <t:beaneditform t:id="account"/>
        </t:block>
    </body>
</html>]]></source>

                <p>
                    So we end up with a display of the Account's properties, and a link to activate edit mode.
                    In edit mode, we use the other block and show a BeanEditForm.
                </p>

            </subsection>

            <subsection name="ViewAccount.java">
                <source><![CDATA[
public class ViewAccount
{
    @Persist
    private Account account;

    @Persist
    private boolean editMode;

    @Inject
    private Block edit, view;

    @Inject
    private AccountDAO accountDAO;

    public Account getAccount()
    {
        return account;
    }

    public void setAccount(Account account)
    {
        account = account;
        editMode = false;
    }

    void onSuccess()
    {
         accountDAO.update(_account);

        editMode = false;
    }

    void onActionFromEdit()
    {
        editMode = true;
    }

    public Object getActiveBlock()
    {
        return editMode ? edit : view;
    }
}]]></source>

                <p>
                    The use of the @Inject annotation on a field of type Block is used to access a
                    <code><![CDATA[<t:block>]]></code>
                    element from the template. The field name,
                    stripped of leading underscores, is matched against the block's id.
                </p>

                <p>
                    The rest is concerned with handling the form submission, turning on edit mode,
                    and determining which block will be the one to render.
                </p>


            </subsection>

        </section>

    </body>
</document>