Class method return none why ?

[giants]

Hi there!
i start to wrote my fist class but i got a problem. I post my code here

this is my class: ST7735R.py

Code: Select all

width = 0 
height = 0 
 
class ST7735R:
    
  def __init__(self, w, h):  
      self.width = w
      self.height = h
      
      
  def stampa(self):
      return self.width

in the main.py i wrote :

Code: Select all

from ST7735R import ST7735R 

dspl = ST7735R(128,64)

value = dspl.stampa()
print('value = {}'.format(value))

so the value return None and i don't understand why

Please some one can help me ?

Thank you

Sergio

[pythoncoder]

It works here. I wonder if you were somehow importing a different version of the file. What hardware are you using?

[giants]

I use an ESP32 ESP-32S ESP-WROOM-32

and i use this firmware GENERIC : esp32-idf3-20210202-v1.14.bin

Code: Select all

def stampa(self):
      print("ciao")
      return width

i try to put one print and the print work but still return None

[kevinkk525]

This is not the same code as above and you return "width" which is not in the class. You need to return "self.width" as in your first post.

[giants]

i did but still dosen't work i really don't understand

[jimmo]

Can you paste the exact code you're using?

Probably the best way to test this is at the REPL.

Can you show the output of the following commands:

>>> print(open('ST7735R.py', 'r').read())

>>> print(ST7735R(128, 64).stampa())

[giants]

i just try with REPL and my code works, but still dosen't work on ESP32, i don't know what to think is the ESP32? is the firmware ? really i don't understand

[pythoncoder]

Can I suggest you try again. Create a file foo.py with this contents:

Code: Select all

class ST7735R:
    
  def __init__(self, w, h):  
      self.width = w
      self.height = h
      
      
  def stampa(self):
      return self.width

dspl = ST7735R(128,64)

value = dspl.stampa()
print('value = {}'.format(value))

Copy it to your ESP32. Then, at the REPL, issue

Code: Select all

>>> import foo
value = 128
>>>  

It works here on an ESP32.

[giants]

Soon i can i try
Thank you

[giants]

WORK please can you tell me why ?

Thank you

Sergio