覆盖kivymd

Question

我的MDToolbar位于标签的最上方，我希望标签的文本显示在工具栏下方，并且pos_hint对此不起作用。我想设置标签文本的位置，我也想提供这是我在.kv文件中的代码

<MainScreen>:
    BoxLayout:
        canvas:
            Color:
                rgb: 0, 0, 0, 0
            Rectangle:
                pos: root.pos
                size: root.size
        ScrollView:
            Label:
                text:
                    """
                    A boy and a girl were playing together. The boy had a collection of marbles. The girl has some
                    sweets with her. The boy told the girl that he would give her all his marbles in exchange for the
                    sweets with her. The girl agreed.

                    The boy kept the most beautiful and the biggest marbles with him and gave her the remaining marbles.
                    The girl gave him all her sweets as she promised. That night the girl slept peacefully. But the boy
                    could not sleep as he kept wondering if the girl has hidden some sweets from him the way he had
                    hidden the best marbles from her.

                    Moral of the Story :

                    If you do not give 100 percent in a relationship, you will always kept doubting if the other person
                    has given her / his hundred percent. This is applicable for any relationship like love, employee –
                    employer, friendship, family, countries, etc…
                    """
                font_size: '20sp'
                height: self.texture_size[1]
                size: self.texture_size
                text_size: root.width, None
                size_hint_x: 1.0
                size_hint_y: None
                halign: "auto"
                valign: "middle"
ScreenManager:
    id: screen_manager

    MainScreen:
        name: 'main'

        NavigationLayout:

            ScreenManager:

                Screen:

                    MDToolbar:
                        title: "Story"
                        anchor_title: 'left'
                        pos_hint: {"top": 1}
                        elevation: 10
                        left_action_items: [['menu', lambda x: nav_drawer.set_state()]]


            MDNavigationDrawer:
                title: 'Story A Day'
                id: nav_drawer
                swipe_distance: 10

                ContentNavigationDrawer:
                    id: content_drawer
                    screen_manager: screen_manager
                    nav_drawer: nav_drawer

Answer 1

问题在于您的“ kv”文件具有两个用于构建MainScreen的规则，并且两个规则都正在执行。您应该将这两个规则合而为一，以便可以引用MainScreen的不同部分来帮助定位。例如，将id添加到MDToolbar可以将ScrollView放置在其下方。像这样：

<MainScreen>:
    BoxLayout:
        canvas:
            Color:
                rgb: 0, 0, 0, 0
            Rectangle:
                pos: root.pos
                size: root.size
ScreenManager:
    id: screen_manager

    MainScreen:
        name: 'main'

        NavigationLayout:

            ScreenManager:

                Screen:

                    MDToolbar:
                        id: toolbar  # id for use below
                        title: "Story"
                        anchor_title: 'left'
                        pos_hint: {"top": 1}
                        elevation: 10
                        left_action_items: [['menu', lambda x: nav_drawer.set_state()]]

                    ScrollView:
                        #  use toolbar id to position the ScrollView
                        pos_hint: {'top': 1.0 - toolbar.height / self.parent.height}
                        Label:
                            text:
                                """
                                A boy and a girl were playing together. The boy had a collection of marbles. The girl has some
                                sweets with her. The boy told the girl that he would give her all his marbles in exchange for the
                                sweets with her. The girl agreed.
.
.
.

您的kv文件的操作过于复杂。我没有做任何简化，因为您可能有这样做的理由。