mpg.kv

<MPGWidget>:
    # RelativeLayout
    on_selected_axis: root.selected_index= ord(args[1]) - ord('X') if args[1] != 'Fo' else -1
    on_selected_index: root.index_changed(args[1])

    BoxLayout:
        orientation: 'horizontal'
        pos_hint: {'top': 1.0}
        size_hint_y: None
        height: 56
        padding: 8
        spacing: 8
        ToggleButton:
            text: 'X'
            group: 'axis'
            state: 'down'
            size_hint_y: None
            height: 40
            on_state: if self.state == 'down': root.selected_axis= self.text
        ToggleButton:
            text: 'Y'
            group: 'axis'
            size_hint_y: None
            height: 40
            on_state: if self.state == 'down': root.selected_axis= self.text
        ToggleButton:
            text: 'Z'
            group: 'axis'
            size_hint_y: None
            height: 40
            on_state: if self.state == 'down': root.selected_axis= self.text
        ToggleButton:
            id: Fo
            text: 'Fo'
            group: 'axis'
            size_hint_y: None
            height: 40
            on_state: if self.state == 'down': root.selected_axis= self.text
        GridLayout:
            cols: 2
            CheckBox:
                id: x01
                group: 'cb1'
            Label:
                text: '0.01'
                size_hint_x: None
                width: self.texture_size[0]
            CheckBox:
                id: x001
                group: 'cb1'
            Label:
                text: '0.001'
                size_hint_x: None
                width: self.texture_size[0]

    Label:
        pos_hint: {'top': 0.92}
        id: pos_lab
        text: '{:+09.3f}'.format(root.last_pos) if root.selected_index >= 0 else '{:9.0f}'.format(root.last_pos)
        font_size: '70sp'
        font_name: "data/fonts/RobotoMono-Regular.ttf"
        size_hint_y: None
        height: self.texture_size[1]

    Knob:
        pos_hint: {'center_x': 0.5, 'y': -0.03}
        size: 300, 300
        min: 0
        max: 100
        step: 1
        value: 0  # Default position of knob.
        knobimg_source: "img/knob_metal.png"  # Knob texture
        show_label: False  # Show central label
        show_marker: False  # Do not show surrounding marker
        on_tick: root.handle_change(self.ticks)
        #on_release: root.handle_action()

    Button:
        pos_hint: {'right': 0.99, 'y': 0.01}
        disabled: mpg_mode_tb.state == 'down'
        text: 'Run'
        size_hint: None, None
        size: dp(80), dp(40)
        on_press: root.handle_action()

    Button:
        pos_hint: {'right': 0.99, 'y': 0.6}
        text: 'Zero'
        size_hint: None, None
        size: dp(80), dp(40)
        on_press: root.last_pos= 0
        disabled: Fo.state == 'down'

    ToggleButton:
        id: mpg_mode_tb
        pos_hint: {'x': 0.01, 'y': 0.01}
        text: 'MPG Mode'
        size_hint: None, None
        size: dp(80), dp(40)
        disabled: Fo.state == 'down'

    ToggleButton:
        id: abs_mode_tb
        disabled: mpg_mode_tb.state == 'down' or Fo.state == 'down'
        pos_hint: {'x': 0.01, 'y': 0.6}
        text: 'ABS' if self.state == 'down' else 'REL'
        size_hint: None, None
        size: dp(80), dp(40)
        on_state: root.abs_mode_changed()