Kivy Carousel from a button - events

Question

What is missing in this code to running carousel??
I´m trying to conect the carousel in a button. When I run, it´s show a button, but the on_press nothing happens.
What is missing in this code to running carousel??
Builder.load_string('''
<tela>:
Button:
text: 'ir'
font_size: 32
size_hint: None, None
pos_hint: {'right': 1}
size: 150, 50
on_press: root.ida()
''')
class acesso(BoxLayout):
def ida(self):
self.clear_widgets()
self.add_widget(tela1())
class tela(BoxLayout):
def ida(self):
self.parent.ida()
class tela1(App,Widget):
def livro(self):
carousel = Carousel(direction='right',loop='true')
for i in range(1,5):
src = "images/%d.png" % i
image = Image(source=src,pos=(1,10), size=(1250, 635))
carousel.add_widget(image)
return carousel
class CarroselApp(App):
def build(self):
self.acesso = acesso()
self.acesso.add_widget(tela())
return self.acesso
if __name__ == "__main__":
CarroselApp().run()

Answer 1

There is multiples issue with your code:
You inherith from App and Widget for tela1. I don't know the effect of that, but this would be wrong somehow. Thoses are not meant to be combined. Your CarroselApp is already here.
Your tela1 widget have a livro() method, but is never called. Plus, you create a widget Carousel without really adding it to the tela1.
tela inherith from a Widget, so it wont layout the children. I'm 200% this would not give what you wished in the first place.
I guess if you replace tela1 with this code, it might works:
class tela1(FloatLayout):
def __init__(self, **kwargs):
super(tela1, self).__init__(**kwargs)
self.add_widget(self.livro())
def livro(self):
carousel = Carousel(direction='right',loop='true')
for i in range(1,5):
src = "images/%d.png" % i
image = Image(source=src,pos=(1,10), size=(1250, 635))
carousel.add_widget(image)
return carousel
Note: please consider pep8 for your code. Using lowercase for class name is not usual and confusing.