Test.kv

WindowManager:
    InputWindow:
    ShearWindow:
    MomentWindow:
    AxialWindow:
    DeflectionWindow:

<BackgroundColor@Widget>
    background_color: 1, 1, 1, 1
    canvas.before:
        Color:
            rgba: root.background_color
        Rectangle:
            size: self.size
            pos: self.pos

<BackgroundLabel@Label+BackgroundColor>
    background_color: 0, 0, 0, 0

<MomentButton@Button>
    size_hint: (0.2, 0.2)
    text: "Bending Moment graph"
    on_release: app.root.current = "Moment"

<AxialButton@Button>
    size_hint: (0.2, 0.2)
    text: "Axial Stress graph"
    on_release: app.root.current = "Axial"

<ShearButton@Button>
    size_hint: (0.2, 0.2)
    text: "Shear stress graph"
    on_release: app.root.current = "Shear"

<DeflectionButton@Button>
    size_hint: (0.2, 0.2)
    text: "Deflection graph"
    on_release: app.root.current = "Deflection"

<Indeterminate_load>
    Label:
        text: "At least either a Fixed support or a Pin Support (with another) are required"
        size_hint: (1,1)
        pos_hint: {'x':0,'y':0}

<Lengthchange_Error>
    Label:
        text: "Length can't be changed after it has been entered"
        size_hint: (1,1)
        pos_hint: {'x':0,'y':0}

<Non_Float_Error>
    Label:
        text: "Only numbers are allowed"
        size_hint: (1,1)
        pos_hint: {'x':0,'y':0}

<Length_Error>
    Label:
        text: "The length inputted must be greater than 0"
        size_hint: (1,1)
        pos_hint: {'x':0,'y':0}

<Position_Error>
    Label:
        text: "The distance inputted must be between 0 and the length of the beam"
        size_hint: (1,1)
        pos_hint: {'x':0,'y':0}

<Before_Length_Error>
    Label:
        text: "A length must be specified before adding supports or loads"
        size_hint: (1,1)
        pos_hint: {'x':0,'y':0}

<Non_Equation_Error>
    Label:
        text: "Only numbers are allowed"
        size_hint: (1,1)
        pos_hint: {'x':0,'y':0}

<Support_Input>
    support_dis: support_dis_input
    Label:
        text: "Distance from LHS of support (m)"
        size_hint:(1, 0.3)
        pos_hint: {'top': 1, 'x': 0}
    TextInput:
        size_hint: (1, 0.3)
        pos_hint: {'y': 0.4, 'x': 0}
        id: support_dis_input
    Button:
        size_hint: (1, 0.4)
        pos_hint: {'y': 0, 'x': 0}
        text: "Input Support"
        on_release: root.inputsupport()

<Moment_Input>
    moment_mag: moment_mag_input
    moment_dis: moment_dis_input
    Label:
        size_hint: (0.5, 0.3)
        pos_hint: {'top': 1, 'x': 0}
        text: "Distance from LHS of moment (m)"
    TextInput:
        id: moment_dis_input
        pos_hint: {'top': 1, 'x': 0.5}
        size_hint: (0.5, 0.3)
    Label:
        size_hint: (0.5, 0.3)
        pos_hint: {'x': 0, 'y': 0.4}
        text: "Magnitude of Moment (kNm)"
    TextInput:
        id: moment_mag_input
        pos_hint: {'x': 0.5, 'y': 0.4}
        size_hint: (0.5, 0.3)
    Button:
        pos_hint: {'x': 0, 'y': 0}
        size_hint: (1, 0.4)
        text: "Input Moment"
        on_release: root.inputmoment()

<Point_Input>
    point_mag: point_mag_input
    point_dis: point_dis_input
    point_angle: point_angle_input

    Label:
        size_hint: (0.5, 0.25)
        pos_hint: {'top': 1, 'x': 0}
        text: "Distance from LHS of load (m)"
    TextInput:
        id: point_dis_input
        pos_hint: {'top': 1, 'x': 0.5}
        size_hint: (0.5, 0.25)
    Label:
        size_hint: (0.5, 0.25)
        pos_hint: {'x': 0, 'y': 0.5}
        text: "Magnitude of Point Load (kN)"
    TextInput:
        id: point_mag_input
        pos_hint: {'x': 0.5, 'y': 0.5}
        size_hint: (0.5, 0.25)
    Label:
        text: "Angle of Point load (degrees)"
        size_hint: (0.5, 0.25)
        pos_hint: {'x': 0 , 'y': 0.25}
    TextInput:
        id: point_angle_input
        size_hint: (0.5, 0.25)
        pos_hint: {'x': 0.5 , 'y': 0.25}
    Button:
        pos_hint: {'x': 0, 'y': 0}
        size_hint: (1, 0.25)
        text: "Input Point Load"
        on_release: root.inputpoint()

<Distributed_Input>
    dis_start: dis_start_input
    dis_end: dis_end_input
    dis_startv: dis_startv_input
    dis_endv: dis_endv_input

    Label:
        text: "Distributed Load Start (from LHS in m)"
        size_hint: (0.5, 0.25)
        pos_hint: {'top': 1, 'x': 0}

    TextInput:
        id: dis_start_input
        size_hint: (0.5, 0.25)
        pos_hint: {'top': 1, 'x': 0.5}

    Label:
        text: "Distributed Load End (from LHS in m)"
        pos_hint: {'y': 0.5, 'x': 0}
        size_hint: (0.5, 0.25)

    TextInput:
        id: dis_end_input
        pos_hint: {'y': 0.5, 'x': 0.5}
        size_hint: (0.5, 0.25)

    Label:
        text: "Start value (kN)"
        pos_hint: {'y': 0.25, 'x': 0}
        size_hint: (0.25, 0.25)

    TextInput:
        id: dis_startv_input
        pos_hint: {'y': 0.25, 'x': 0.25}
        size_hint: (0.25, 0.25)

    Label:
        text: "End value (kN)"
        pos_hint: {'y': 0.25, 'x': 0.5}
        size_hint: (0.25, 0.25)

    TextInput:
        id: dis_endv_input
        pos_hint: {'y': 0.25, 'x': 0.75}
        size_hint: (0.25, 0.25)

    Button:
        text: "Input distributed loads"
        pos_hint: {'y': 0, 'x': 0}
        size_hint: (1, 0.25)
        on_release: root.inputdis()

<InputWindow>:
    on_enter: root.clear()

    name: "input"
    length: lengthinput

    FloatLayout:

        BackgroundLabel:
            pos_hint: {'top': 1,'x': 0}
            size_hint: (0.6, 0.15)
            background_color: 0.1, 0.0, 0.6, 1
            text: "Current Beam"

        Button:
            pos_hint: {'x':0, 'y':0.75}
            size_hint: (0.2,0.1)
            text: "Update Drawing"
            on_release: root.update_drawing()

        Button:
            pos_hint: {'x':0.4, 'y':0.75}
            size_hint: (0.2, 0.1)
            text: "Reset"
            on_release: root.clear()

        BackgroundLabel:
            pos_hint: {'top': 1,'x': 0.6}
            size_hint: (0.4, 0.15)
            background_color: 0, 0.4, 0.5, 1
            text: "Input:"

        GridLayout:
            size_hint: (0.4, 0.65)
            pos_hint: {'x': 0.6, 'y': 0.2}
            cols: 2

            Button:
                text: "Fixed Support"
                on_release: root.supportbtn("Fixed")

            Button:
                text: "Pin Support"
                on_release: root.supportbtn("Pin")

            Button:
                text: "Roller Support"
                on_release: root.supportbtn("Roller")

            Button:
                on_release: root.pointbtn()
                text: "Point Load"

            Button:
                text: "Moment"
                on_release: root.momentbtn()

            Button:
                on_release: root.DLbtn()
                text: "Distributed Load"

            Button:
                text: "Length (m) :"
                on_release: root.lengthbtn()

            TextInput:
                id: lengthinput

        Button:
            pos_hint: {'x': 0.6, 'y':0}
            size_hint: (0.4, 0.2)
            text: "Calculate"
            on_release: root.load_check()


<ShearWindow>:
    name: "Shear"
    min_value: min_value
    max_value: max_value

    on_enter: root.eqprint()
    on_leave: root.eqremove()

    FloatLayout:

        Label:
            pos_hint: {'x': 0.8, 'y': 0.8}
            size_hint: (0.2, 0.1)
            id: min_value

        Label:
            pos_hint: {'x': 0.0, 'y':0.0}
            size_hint: (0.7, 0.05)
            text: "Negative: Shear stress is downwards | Positive: Shear stress is upwards"

        Label:
            pos_hint: {'x': 0.8, 'y': 0.9}
            size_hint: (0.2, 0.1)
            id: max_value

        AxialButton:
            pos_hint: {'x': 0.8, 'y': 0.6}

        MomentButton:
            pos_hint: {'x': 0.8, 'y': 0.4}

        DeflectionButton:
            pos_hint: {'x': 0.8, 'y': 0.2}

        Button:
            pos_hint: {'x': 0.8, 'y': 0}
            size_hint: (0.2, 0.2)
            text: "Calculate Another Beam"
            on_release: app.root.current = "input"

<MomentWindow>:
    name: "Moment"
    min_value: min_value
    max_value: max_value

    on_enter: root.eqprint()
    on_leave: root.eqremove()

    FloatLayout:

        Label:
            pos_hint: {'x': 0.0, 'y':0.0}
            size_hint: (0.7, 0.05)
            text: "Negative: Hogging (curves in U shape) | Positive: Sagging (curves in n shape)"

        Label:
            pos_hint: {'x': 0.8, 'y': 0.8}
            size_hint: (0.2, 0.1)
            id: min_value

        Label:
            pos_hint: {'x': 0.8, 'y': 0.9}
            size_hint: (0.2, 0.1)
            id: max_value

        ShearButton:
            pos_hint: {'x': 0.8, 'y': 0.4}

        AxialButton:
            pos_hint: {'x': 0.8, 'y': 0.6}

        DeflectionButton:
            pos_hint: {'x': 0.8, 'y': 0.2}

        Button:
            pos_hint: {'x': 0.8, 'y': 0}
            size_hint: (0.2, 0.2)
            text: "Calculate Another Beam"
            on_release: app.root.current = "input"



<DeflectionWindow>:
    name: "Deflection"
    min_value: min_value
    max_value: max_value

    on_enter: root.eqprint()
    on_leave: root.eqremove()

    FloatLayout:

        Label:
            pos_hint: {'x': 0.8, 'y': 0.8}
            size_hint: (0.2, 0.1)
            id: min_value

        Label:
            pos_hint: {'x': 0.8, 'y': 0.9}
            size_hint: (0.2, 0.1)
            id: max_value

        Label:
            pos_hint: {'x': 0.0, 'y':0.0}
            size_hint: (0.7, 0.05)
            text: "Negative: Distance deflected below beam | Positive: Distance deflected above beam"

        ShearButton:
            pos_hint: {'x': 0.8, 'y': 0.4}

        MomentButton:
            pos_hint: {'x': 0.8, 'y': 0.2}

        AxialButton:
            pos_hint: {'x': 0.8, 'y': 0.6}

        Button:
            pos_hint: {'x': 0.8, 'y': 0}
            size_hint: (0.2, 0.2)
            text: "Calculate Another Beam"
            on_release: app.root.current = "input"

<AxialWindow>:
    name: "Axial"
    min_value: min_value
    max_value: max_value

    on_enter: root.eqprint()
    on_leave: root.eqremove()

    FloatLayout:

        Label:
            pos_hint: {'x': 0.0, 'y':0.0}
            size_hint: (0.7, 0.05)
            text: "Negative: Axial stress is towards LHS | Positive: Axial stress is towards RHS"

        Label:
            pos_hint: {'x': 0.8, 'y': 0.8}
            size_hint: (0.2, 0.1)
            id: min_value

        Label:
            pos_hint: {'x': 0.8, 'y': 0.9}
            size_hint: (0.2, 0.1)
            id: max_value

        ShearButton:
            pos_hint: {'x': 0.8, 'y': 0.6}

        MomentButton:
            pos_hint: {'x': 0.8, 'y': 0.4}

        DeflectionButton:
            pos_hint: {'x': 0.8, 'y': 0.2}

        Button:
            pos_hint: {'x': 0.8, 'y': 0}
            size_hint: (0.2, 0.2)
            text: "Calculate Another Beam"
            on_release: app.root.current = "input"