Through
/servicesNS/nobody/MYAPP/admin/nav/default
I can access the navigation bar content of my app. I now want to be able to change this via a setup page. Displaying eai:data works fine, however when trying to save on the setup page, I get an error saying
"Cannot find item for POST arg_name="/admin/nav/default/eai%3Adata""
My setup.xml:
<setup>
<block title="Nav" endpoint="admin/nav" entity="default">
<input field="eai:data">
<label>$name$</label>
<type>text</type>
</input>
</block>
</setup>
Assuming I understood your question correctly, I was able to update the default.xml for the 'search' app using:
cat test.xml
<nav search_view="search" color="#5CC05A">
<view name="search" default="true" />
<view name="analytics_workspace" />
<view name="datasets" />
<view name="reports" />
<view name="alerts" />
<view name="dashboards" />
</nav>
curl -ks -u admin:"${pw}" https://localhost:8089/servicesNS/nobody/search/data/ui/nav/default --data-urlencode eai:data@test.xml