box2.kv

BoxLayoutExample:
<BoxLayoutExample>:
    orientation: "horizontal"
    Button:
        text: "Hi"

        size_hint: .5, .5
        # size: "100dp", "60dp"
        # width: "100dp"
        # height: "60dp"
        # x, center_x, right
        # y, center_y, top
        pos_hint: { "center_y": .5 }

    Button:
        text: "Happy"
    Label:
        text: "Learning"