Understanding block__*() delegate methods

Archived from the Xataface Users forum.

kedoin — Wed Apr 23, 2008 12:19 pm

In my Xataface app, I have a ‘people’ table. I wanted to create a new action which will allow users to send email to a result set from the ‘people’ table. To create the form for this, I wanted to use HTML_QuickForm, so I decided to implement block__main_section() in tables/people.php.

This seems to work. When I use my email action, the form I’ve begun to specify appears. Now here’s where I get confused. I would think that since I am overriding this block__ method, that the form would end up showing up on all pages for the ‘people’ table. But, I haven’t found it showing up on any of the oages such as “details”, “list”, “new record”. I’m not complaining as I only wanted them to show up for my email action. However, I don’t understand why the main_section I defined in the delegate isn’t showing up in more places. I guess another way of asking my question is how do I make sure this email form only appears in my email action and not in the main_section of some other action on the ‘people’ table?

Thank you,

-Rob

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shannah — Thu Apr 24, 2008 9:10 am

This can be a little confusing. A slot can be overridden in two ways.

1. implement the block__slotname() method in the delegate class.

2. Inherit from the template using the {use_macro} tag, and then fill the slot using the {fill_slot} tag.

If a template is derived from another template using the {use_macro} tag, and it overrides a slot via the {fill_slot} tag, then effectively the slot is no longer available to be overridden, unless the template defines a new slot of the same name.

e.g.

MyTemplate.html extends from Dataface_Main_Template.html:

Code: Select all

`{use_macro file=”Dataface_Main_Template.html”}
    {fill_slot name=”main_section”}

        My custom content in the main section
    {/fill_slot}
{/use_macro}`

Now we can no longer override the main_section slot for this template, because it has already been used.

We could redesign this template to still allow us to override the main_section slot:

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{use_macro file="Dataface_Main_Template.html"}     {fill_slot name="main_section"}         {define_slot name="main_section"}             My custom content in the main section          {/define_slot}     {/fill_slot} {/use_macro}

This is why your block__main_section() is not overriding many of the templates. It is because those templates already implement that slot.

If you are doing a custom action for your email form, it is better to create a template that inherits from the Dataface_Main_Template.html template than to implement the block__main_section() method. That way you don’t have to worry about undesired side-effects.