I'm trying to implement a scrollbar in my app but I don't know how to do it. Can you help me? I tried to follow some tutorials, but I didn't manage to find one that explained clearly what to do. This is a "collage" made by all those tutorials.

Here's the code.

ScrollView:
        size_hint: 1, None
        size: root.width, root.height
        do_scroll_x: False

        GridLayout:
            id: output
            cols: 1
            height: self.minimum_height

            # Then i tried to add some buttons to see if it worked, but without success.

Thank you in advance.