M5Stack LVGL, Any Documentation?

AhmadAgb

I was looking at: https://docs.m5stack.com/en/mpy/display/m5stack_lvgl on which provides few examples on how to draw on my CORE2 display using MicroPython.

While it provides few examples, in my case it's not enough at all. Few things I'm interested in (Kindly relate to all sub-questions in your answer):

As an example, How can I look at the inner implementation of: M5Textarea? I would like to see which parameters each function takes, which of them are optional, how it's implemented (so I can write something similar) etc...
I want to write a new class deriving from Element Base Class: M5Obj How can I do that without knowing how the base class is implemented?
Where can I find the full list of Objects? From my experience I've discovered few which aren't mentioned in that page at all. For example, I want to see how can I draw a graph.
I found the following function which draws rectangle on the screen:

temp = lcd.triangle(19, 10, 300, 40, 90, 200, color=0xcc0000)

which doesn't return anything, ie temp is a NoneType Object, In this case how can I delete that rectangle? as I don't have a reference to M5Obj Object I can't write temp.delete()

Note: I can't just color the whole display in white as there could be complex elements in the background.