Kivy: how to display a list with variable rows in Kivy with a RecycleView?

Question

I'm new to Python and Kivy, and I need to display a list with variable rows, I'm trying with a recycle view, but I think I'm doing it wrong, and I don't know how it works at all. here's my code

class Introduccion(Screen):
numbers = ObjectProperty()
number_list = ObjectProperty([])

def Add_ToList(self):
    dat = self.numbers.text
    self.number_list.append([dat])

and my.kv file

<Introduccion>:
    numbers: numbers_input
    number_list: number_list_view
    RelativeLayout:
        pos_hint:{'center_y': 0.8, 'center_x':0.5}
        size_hint: None, None
        size: 700, 200
        pos: 200, 100
        canvas.before:
            Color:
                rgba: 1, 0.1, 0.2, 0
            Rectangle:
                pos: 0,0
                size: self.size
        TextInput:
            id: numbers_input
            size_hint: None, None
            pos: 520, 66
            size: 70, 30
            multiline: False
        Button:
            size_hint: None, None
            pos: 600, 66
            size: 50, 30
            text: "añadir"
            on_press: root.Add_ToList()
    BoxLayout:
        pos_hint:{'center_y': 0.8, 'center_x':0.5}
        size_hint: None, None
        size: 10, 10
        pos: 200, 100
        RecycleView:
            id: number_list_view
            viewclass: 'Label'
            RecycleBoxLayout:
                default_size: None, dp(26)
                default_size_hint: 1, None
                size_hint_y: None
                height: self.minimum_height
                orientation: 'vertical'

Answer 1

The data of a RecycleView is a list of dictionaries with viewclass attributes as keys and the value of that attribute as values. Since your viewclass is Label , an appropriate key in the data dictionary is text . So your Introduccion class can be:

class Introduccion(Screen):
    numbers = ObjectProperty()
    number_list = ObjectProperty()

    def Add_ToList(self):
        self.number_list.data.append({'text': str(self.numbers.text)})

The Add_ToList() method adds a new dictionary to the RecycleView data on each call. In each case, the key is text (referring to the text attribute of Label ), and the value is whatever is in the TextInput .