helpscreen.kv

<HelpScreenLayout>
    BoxLayout:
        canvas.before:  # background image of help screen
            Rectangle:
                size: self.size
                pos: self.pos
                source: 'res/system/white_background.jpg'
        BoxLayout:
            size_hint_x: .3
            orientation: 'vertical'
            Widget:
                size_hint_y: .125
            BoxLayout:
                size_hint_y: .15
                Widget:
                    size_hint_x: .3
                Button:  # button for quitting the user help screen
                    text: 'BACK'
                    bold: True
                    on_release: root.back()
                Widget:
                    size_hint_x: .2
            Widget:
        BoxLayout:
            orientation: 'vertical'
            Widget:
                size_hint_y: .1
            Label:
                color: 0, 0, 0, 1
                font_size: 45
                text: 'User Help'
                bold: True
                size_hint_y: .15
            BoxLayout:
                size_hint_y: .7
                Widget:
                BoxLayout:  # layout containing 3 buttons for calling a function for each screen's help
                    size_hint_y: .8
                    size_hint_x: .7
                    orientation: 'vertical'
                    spacing: 70
                    Button:
                        text: 'Home Screen'
                        on_release: root.popup_help('res/library/home_screen_help.png')
                    Button:
                        on_release: root.popup_help('res/library/activity_screen_help.png')
                        text: 'Activity Selection'
                    Button:
                        on_release: root.popup_help('res/library/meal_screen_help.png')
                        text: 'Mean Selection'
                Widget:
            Widget:
                size_hint_y: .3
        Widget:
            size_hint_x: .3


<HelpScreen@Screen>:
    name: 'help_screen'
    screen_manager: self.screen_manager

    HelpScreenLayout:
        screen_manager: root.screen_manager