example.py

# I use the following to get all results from a mysql table using sqlalchemy:
def get_all_users(self):
    selectUsers = select(self.Users.UserID, self.Users.UniqueIdentifier, self.Users.DisplayName, self.Users.Status, self.Users.PermissionID)
    with Session(self.engine) as session:
        result = session.execute(selectUsers)
        result = [list(x) for x in result]
        return result
      
# This collects all the rows in my table and returns it as a list.
# In my main.py file:
class SelectableUserRecycleBoxLayout(FocusBehavior, LayoutSelectionBehavior, RecycleBoxLayout):
    ''' Adds selection and focus behaviour to the view. ''' 
    
class SelectableUserBoxLayout(RecycleDataViewBehavior, BoxLayout):
    ''' Add selection support to the Label '''
    index = None
    selected = BooleanProperty(False)
    selectable = BooleanProperty(True)

    def refresh_view_attrs(self, rv, index, data):
        ''' Catch and handle the view changes '''
        self.index = index

        return super(SelectableUserBoxLayout, self).refresh_view_attrs(rv, index, data)

    def on_touch_down(self, touch):
        ''' Add selection on touch down '''
        if super(SelectableUserBoxLayout, self).on_touch_down(touch):
            return True
        if self.collide_point(*touch.pos) and self.selectable:
            return self.parent.select_with_touch(self.index, touch)

    def apply_selection(self, rv, index, is_selected):
        ''' Respond to the selection of items in the view. '''
        self.selected = is_selected
        rv.data[index]['selected'] = self.selected
        if is_selected:
            print("selection changed to {0}".format(rv.data[index]))
            # Here I add data to a second RecycleView that shows all the user's reservations
            app.root.ids.management_scr.resdata.data = [{"resid": str(x[0]),"startTime": str(x[1]), "endTime": str(x[2]), "userId": str(x[3]), "lockerId": str(x[4]), "selected":False} for x in database.get_reservation_by_userid(userid)]
        else:
            print("selection removed for {0}".format(rv.data[index]))
            app.root.ids.management_scr.resdata.data = []
            
class UserListView(RecycleView):
    userdata = ObjectProperty()
    def __init__(self, **kwargs):
        super(UserListView, self).__init__(**kwargs)
        # This is the important part, this populates your RecycleView with data
        self.data = [{"userid": str(x[0]),"uniqueid": x[1], "displayname": str(x[2]), "status": str(x[3]), "permissionid": str(x[4]), "selected":False} for x in database.get_all_users()]
# In my .kv file:
<SelectableUserBoxLayout>:
    # Draw a background to indicate selection
    font_size: '26sp'
    canvas.before:
        Color:
            rgba: (.0, 0.9, .1, .3) if self.selected else (0, 0, 0, 1)
        Rectangle:
            pos: self.pos
            size: self.size
    userid: ""
    displayname: ""
    status: ""
    permissionid: ""
    
    GridLayout:
        cols:4
        Label:
            text: root.userid
            size_hint_x: .1
        Label:
            text: 'Anonymous'
            size_hint_x: .6
        Label:
            text: root.status
            size_hint_x: .1
        Label:
            text: root.permissionid
            size_hint_x: .2
<UserListView>:
    id: userdata
    viewclass: 'SelectableUserBoxLayout'
    SelectableUserRecycleBoxLayout:
        id: controller
        default_size: None, dp(56)
        default_size_hint: 1, None
        size_hint_y: None
        height: self.minimum_height
        orientation: 'vertical'
        multiselect: False
        touch_multiselect: False
        font_size: '26sp'

# inside my screen I add the following:
<Screen>:
    BoxLayout:
      orientation: 'vertical'
      Label:
        size_hint_y: .1
        text: 'User List:'
      Userlistview:
        id: userdata
        size_hint_y: .9
# So when my table has users inside of it, I get a scrollable list with all my users, and is selectable