Matrix with a Playa field which has a Playa Field

Question

To set the stage, I've got 3 Channels: Agenda, Sessions, and Speakers, with a breakdown of the custom field types as follows.

• Agenda contains a Matrix field with 3 columns - the start time, end time, and a Playa field to select the session to add to the time slot
• Sessions contains a title and description field along with a Playa field to choose the Speaker(s) for that session
• Speaker contains several custom fields that describe the speaker.

I'm trying to create the Agenda, and read about a few different options. This is what I have so far, but obviously it's not working.

{exp:channel:entries channel="agenda" dynamic="no" limit="1" show_future_entries="yes" }
<h1>{title}</h1>
{agenda_description}
<h3>{agenda_date_monday format="%l, %F %j"}</h3>
{agenda_monday}
<div class="details_left">{am_start_time format="%g:%i%a"} - {am_end_time format="%g:%i%a"}</div>
<div class="details_right">
    {am_session}<h4><a href="{path={channel_short_name}/{url_title}}">{title}</a></h4>
        {session_speakers}
          <p>{title}</p>
        {/session_speakers}
    {/am_session}
</div>
{/agenda_monday}
{/exp:channel:entries}

Thanks for any suggestions, and please feel free to ask clarifying questions!

Answer 1

As per the Playa docs on nested relationships:

If you need to access a Playa field from within another Playa field, the only way to go about that is through an embedded template:

So in your case:

{exp:channel:entries channel="agenda" dynamic="no" limit="1" show_future_entries="yes" }
    <h1>{title}</h1>
    {agenda_description}
    <h3>{agenda_date_monday format="%l, %F %j"}</h3>
    {agenda_monday}
        <div class="details_left">{am_start_time format="%g:%i%a"} - {am_end_time format="%g:%i%a"}</div>
        <div class="details_right">
            {embed="agenda/_session_listing" entry_ids="{am_session:child_ids}"}
        </div>
    {/agenda_monday}
{/exp:channel:entries}

Then in agenda/_session_listing:

{exp:channel:entries channel="sessions" fixed_order="0|{embed:entry_ids}" dynamic="no" disable=member_data|pagination|categories"}
    <h4><a href="{path={channel_short_name}/{url_title}}">{title}</a></h4>
    {session_speakers}
        <p>{title}</p>
    {/session_speakers}
{/exp:channel:entries}

Another tip: instead of using {path={channel_short_name}/{url_title}}, consider using {comment_url_title_auto_path} (docs).