python - 无法更改 BoxlLayout 的高度

Question

我正在尝试更改嵌套在另一个 BoxLayout 内的 BoxLayout 的高度。我已经尝试了十多种尺寸、尺寸提示和高度的组合，但似乎没有任何效果。问题是无论我对“ContainerBox”BoxLayout 内部的BoxLayout 做什么，这些BoxLayout 的大小始终相同。如何更改嵌套 BoxLayout 的高度？我想使用 kv 语言来设置高度而不是 python 代码。

Python

import kivy
kivy.require('1.7.1')
from kivy.app import App
from kivy.uix.label import Label
from kivy.uix.gridlayout import GridLayout
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.textinput import TextInput
from kivy.uix.widget import Widget
from kivy.properties import ObjectProperty
from kivy.core.window import Window
Window.clearcolor = (1, 1, 1, 1)

class ContainerBox(BoxLayout):
def __init__(self, **kwargs):
    super(ContainerBox, self).__init__(**kwargs)

class Header(BoxLayout):
def __init__(self, **kwargs):
    super(Header, self).__init__(**kwargs)

class Toolbar(BoxLayout):
def __init__(self, **kwargs):
    super(Toolbar, self).__init__(**kwargs)     

class LoginScreen(GridLayout):
    f_username = ObjectProperty(None)
    f_password = ObjectProperty(None)   
    def __init__(self, **kwargs):
        super(LoginScreen, self).__init__(**kwargs)     

class LoginApp(App):
    def build(self):
        return ContainerBox()


if __name__ == '__main__':
    LoginApp().run()

Kv文件

# kivy 1.7.1
<LoginScreen>:
    f_username: username
    f_password: password
    GridLayout:
        size: root.width, 200
        pos: root.pos
        row_default_height: 10
        rows: 3
        cols: 2
        padding: 20
        spacing: 10     
        Label:
            text: 'User Name:'
            color: 0.212, 0.486, 0.169, 1
            font_size: 24
        TextInput:
            id: username
        Label:
            text: 'Password:'
            color: 0.212, 0.486, 0.169, 1
            font_size: 24
        TextInput:
            id: password
            password: True
        Label:
        Button:
            text: 'Login'
            background_normal: 'white_20x20.png'
            background_color: 0.212, 0.486, 0.169, 1
            font_size: 24

<Header>:
    BoxLayout:
        orientation: 'vertical'
        height: 100
        size_hint_x: 1
        size_hint_y: None
        Label:
            text: 'Dealer App'
            color: 0.212, 0.486, 0.169, 1
            font_size: 48


<Toolbar>           
    BoxLayout:
        orientation: 'horizontal'
        height: 36
        size_hint_x: 1
        size_hint_y: None
        pos: root.pos
        spacing: 5  
        Button:
            text: 'One'
            background_normal: 'white_20x20.png'
            background_color: 0.212, 0.486, 0.169, 1
            font_size: 16
        Button:
            text: 'Two'
            background_normal: 'white_20x20.png'
            background_color: 0.212, 0.486, 0.169, 1
        Button:
            text: 'Three'
            background_normal: 'white_20x20.png'
            background_color: 0.212, 0.486, 0.169, 1
        Button:
            text: 'Four'
            background_normal: 'white_20x20.png'
            background_color: 0.212, 0.486, 0.169, 1


<ContainerBox>:
    BoxLayout:
        orientation: 'vertical'
        Header:
        Toolbar:
        LoginScreen:

Answer 1

这是由于您的双重嵌套布局造成的。例如，您有 ContainerBox，它是一个 BoxLayout。因此，您添加到 Header，它扩展了 BoxLayout，但 size_hint 为 (1, 1)!您可以在 Header 内包含的 BoxLayout 上设置 size_hint，但这不会影响 Header 本身。

因此，要解决此问题:删除额外的嵌套布局，如下所示:

<LoginScreen>:
    f_username: username
    f_password: password
    size: root.width, 200
    pos: root.pos
    row_default_height: 10
    rows: 3
    cols: 2
    padding: 20
    spacing: 10     
    Label:
        text: 'User Name:'
        color: 0.212, 0.486, 0.169, 1
        font_size: 24
    TextInput:
        id: username
    Label:
        text: 'Password:'
        color: 0.212, 0.486, 0.169, 1
        font_size: 24
    TextInput:
        id: password
        password: True
    Label:
    Button:
        text: 'Login'
        background_normal: 'white_20x20.png'
        background_color: 0.212, 0.486, 0.169, 1
        font_size: 24

<Header>:
    orientation: 'vertical'
    height: 100
    size_hint_x: 1
    size_hint_y: None
    Label:
        text: 'Dealer App'
        color: 0.212, 0.486, 0.169, 1
        font_size: 48


<Toolbar>           
    orientation: 'horizontal'
    height: 36
    size_hint_x: 1
    size_hint_y: None
    pos: root.pos
    spacing: 5  
    Button:
        text: 'One'
        background_normal: 'white_20x20.png'
        background_color: 0.212, 0.486, 0.169, 1
        font_size: 16
    Button:
        text: 'Two'
        background_normal: 'white_20x20.png'
        background_color: 0.212, 0.486, 0.169, 1
    Button:
        text: 'Three'
        background_normal: 'white_20x20.png'
        background_color: 0.212, 0.486, 0.169, 1
    Button:
        text: 'Four'
        background_normal: 'white_20x20.png'
        background_color: 0.212, 0.486, 0.169, 1