Joomla 404 component not found (custom component)

Question

I am trying to create a custom component in my Joomla backend, so I created this xml file:

<?xml version="1.0" encoding="utf-8"?>
<extension type="component" version="3.8.1" method="upgrade">
<name>administratie</name>
<creationDate>2019-04-09</creationDate>
<author>Twan</author>
<authorEmail>[email protected]</authorEmail>
<version>3.8.1</version>
<description>Administratie dashboard</description>
<administration>
<menu>administratie</menu>

<files folder="components/com_administratie/admin">
<file>administratie.php</file>
</files>
</administration>
</extension>

And installed it, which worked, the administratie link is added in my components drop down, except when I click on it, the page shows a 404 component not found error.

Maybe I wrote something wrong in my xml file? I can't find what it is. This is my folder structure:

administrator
-components
--com_administratie
---admin
---administratie.xml
----administratie.php (this file has a simple echo in it)

I already tried refreshing the cache but I keep getting the same error.

I am on Joomla version: Joomla! 3.8.1 Stable

Answer 1

From your question it is ambiguous whether your entry file is inside the admin subfolder or not. It should be in the com_administratie folder if it isn't. Also your xml files declaration looks odd:

<files folder="components/com_administratie/admin">
<file>administratie.php</file>
</files>

The folder attribute should just be site or admin. While sub folders can be included as folder elements. So something like the following:

<files folder="admin">
  <filename>administratie.php</filename>
  <folder>admin</folder>
</files>

If you're only using discovery to install then the file declarations don't matter as much. In any case, the component will look at

/administrator/components/com_administratie/administratie.php

as the default entry file without much prompting.