How to learn to understand CMS code?

Question

CMS

I've taken a couple of tutorials and read a couple of PHP books. Then I pulled the layout on joomla, joomshopping. And then I tried to make a joomla component on my own and then big problems began. I can't understand anything in joomla core code. Functions call other functions, those third ones, and so on a huge number of times. In structure MVC too I can understand nothing. The PHP MVC tutorials take up very little space and provide a primitive example at best. The code for PHP tutorials and tasks correlates with the CMS code like an ant with an elephant. I installed PHP Storm, it allows you to jump between functions, but when you start jumping, you don’t understand where the end is and after a couple of hours you forget where you started from. Please tell me how to approach the study of CMS, where to start and how to finish. It doesn't matter what kind of CMS it is. I think the approaches are the same everywhere. Maybe you can recommend good learning materials on PHP, etc. Otherwise, I have a feeling that I studied PHP in vain, I can’t use it for CMS, but I can solve primitive learning problems.

Answer 1

Read the code and read again. Read what Design Patterns are and what they are. In what order the code works, what jumps where, what data is transferred where in what form can be easily tracked in the debugger. Set up phpstorm + xdebug and go.
MVC is implemented differently everywhere, but the basic concept does not change. Very often, in all sorts of tutorials, they do not cover enough, or do not cover the topic of Routing (routes) at all, although this can be said to be the most basic and important in the implementation of MVC. Try to write your own mini-engine the way you understand what MVC is -
understanding will come right away.

Answer 2

CMS has usually joomla API not exception https://api.joomla.org/