Check playa:child_ids against entry_id || Execute a Matric Column only if XYZ in the first

Question

I have a Matrix field as a Low-Variable. It contains two columns, each Playa-Fields.

First Playa-Field: All my sites Pages from my "Page"-Channel. Second Playa-Field: Every Sidebar-Block from my "Sidebar"-Channel.

I want to control all my Sidebars from one place with this structure. It allows me to create Sidebar-Groups through rows and even re-use Sidebar-Groups for two sites.

The problem: How can I check my {entry_id} (of the Page) against the {entry_id} of the first playa-field to check if I should execute this sidebar row?

I want something like below, but obviously it doesn't work. Who knows a work-around?

{exp:low_variables:parse var="lv_sidebar_pages" var_prefix="matrix"}

        {if {matrix:cell_pages:child_ids} CONTAINS {embed:page_id}}
                    {matrix:cell_sidebars}
                    {!-- Sidebar-Code --}
                    {/matrix:cell_sidebars}
        {/if}
{/exp:low_variables:parse}

I also thought about a possibility to check normally in the first Playa-Field and then skip aka. break this loop of the Matrix-Field:

    {exp:low_variables:parse var="lv_sidebar_pages" var_prefix="matrix"}

        {matrix:cell_pages}
            {if {embed:page_id} != {entry_id}} 
                BREAK THIS MATRIX LOOP.. and jump to the next row..
            {/if}
        {matrix:cell_pages}

        {matrix:cell_sidebars}
            ..so this code isn't executed
        {/matrix:cell_sidebars}
{/exp:low_variables:parse}

Thanks for the help.

Answer 1

You can limit your Matrix field to only show rows that include the current page’s entry_id using Matrix’s search param like so:

search:cell_pages="[{entry_id}]"

Just in case you might have accidentally added the same page to multiple Matrix rows, it’s probably worth throwing a limit="1" in there too.

So to throw it all together:

{exp:low_variables:parse var="lv_sidebar_pages"
                         var_prefix="matrix"
                         search:cell_pages="[{entry_id}]"
                         limit="1"}

    {matrix:cell_sidebars}
        {!-- Sidebar-Code --}
    {/matrix:cell_sidebars}

{/exp:low_variables:parse}

Depending on what else is going on in your template, the var_prefix probably isn’t necessary, but it doesn’t hurt so I left it in.