design.kv

<LabeledInput@BoxLayout>:
    cols: 2
    pos_hint: {"center_x": 0.5}
    text: ""
    Widget:
    Label:
        size_hint: (None, None)
        text: root.text
        width: 200
        height: 30
    TextInput:
        size_hint: (None, None)
        width: 400
        height: 30
        #multiline: False
    Widget:


GUILayout:
    size: root.width, root.height
    #textbox_setups: textbox_setups
    border: 20



<LoginScreen>:
    name: "login_page"
    GridLayout:
        canvas.before:
            Rectangle:
                pos: self.pos
                size: self.size
                source: 'Images/black.jpg'
        cols: 1
        row_default_height: '30dp'

        spacing: 20, 20
        LabeledInput:
            id: email
            text: "Your EMail"
            size: root.width - 200, 30
        LabeledInput:
            id: password
            text: "Password"
            size: root.width - 200, 30
        Widget:
            size_hint: None, None
            size: root.width, root.height / 4
        Label:
            text: "Choose delivery mode:"
        BoxLayout:
            orientation: "horizontal"
            columns: 2
            allow_stretch: True
            ToggleButton:
                color: 0.2, 0.2, 0.2, 1
                background_normal: "button1.png"
                background_down: "button2.png"
                borders: 15, 15, 15, 15
                group: "means of connection"
                text: "Phone"
                size_hint: (1, 0.4)
                pos_hint: {'top' : 0.5}
                on_release: root.set_comm_mode("phone")

            ToggleButton:
                color: 0.2, 0.2, 0.2, 1
                background_normal: "button1.png"
                background_down: "button2.png"
                borders: 15, 15, 15, 15
                group: "means of connection"
                text: "Email"
                size_hint: (1, 0.4)
                pos_hint: {'top' : 0.5}
                on_release: root.set_comm_mode("email")

<SetupScreen>:
    name: "setup_page"

    GridLayout:
        id: setup_page
        canvas.before:
            Rectangle:
                pos: self.pos
                size: self.size
                source: 'Images/black.jpg'

        cols: 1
        pos: 100, 100
        spacing: 10, 10
        padding: 50, 50
        size_hint: (None, None)
        size: (root.width, root.height)
        pos_hint: {"center_x": 0.5, "center_y": 0.5}

        GridLayout:
            id: textbox_setups
            cols: 3
            spacing: 30, 10
            padding: 30, 50
            size_hint: (1, 1)
            size: (root.width, root.height - 100)

        PromptAddNew:
            height: 0.4 * root.height

<SendScreen>:
    name: "send_page"

    entry_fields_box_layout: entry_fields
    BoxLayout:
        id: send_page
        canvas.before:
            Rectangle:
                pos: self.pos
                size: self.size
                source: 'Images/black.jpg'
        columns: 1
        orientation: "vertical"
        allow_stretch: True
        spacing: 10
        padding: 10
        #size: root.width, root.height

        BoxLayout:
            orientation: "horizontal"
            allow_stretch: True
            spacing: 40
            padding: 10
            size: 100, 40

            Label:
                text: "Choose a means of communication:"
                pos_hint: { 'top' : 1}
                size_hint: (1, None)
                height: 30

        BoxLayout:
            id: entry_fields
            orientation: "horizontal"
            allow_stretch: True
            spacing: 40
            padding: 10
            size: root.width, root.height*0.7

        RoundedButton:
            id: button
            text: "Send"
            pos_hint: {"center_x": 0.5}
            size_hint: (0.6, 0.2)
            on_press: root.submit()


<InProgressScreen>:
    name: "in_progress_page"
    ProgressBar:
        id: progress_bar
        value: 0
        min: 0
        max: 100
        pos_hint: {"center_x": 0.5}
        size_hint: 0.8, 0.2
    Label:
        canvas.before:
            Rectangle:
                pos: self.pos
                size: self.size
                source: 'text_background.png'

<FileSelector@BoxLayout>:
    orientation: "vertical"
    file_chooser_type: root.file_chooser_type
    cols: 1
    BoxLayout:
        orienttion: "horizontal"
        cols: 2
        Button:
            id: select_file_button
            text: "Select"
        TextInput:
            id: file_name
            multiline: False
    FileChooserListView:
        id: files
        on_selection:
            if self.selection: select_file_button.text = "Select " + self.selection[0]
            else: select_file_button.text = "Select a file"