如何在KivyMD中更改MDFloatingActionButtonSpeedDial中的锚点值？

Question

我一直在与 kivymd 合作开发移动应用程序。但我遇到了有关 MDFloatingActionButtonSpeedDial 的问题。我想将 MDFloatingActionButtonSpeedDial 中的锚点值设置为“left”（对于某些按钮）和“right”（对于某些按钮）。因此，我修改了模块“kivymd.uix.button”中的MDFloatingActionButtonSpeedDial类，并在假定OptionProperty的“anchor”中添加了更多选项。除此之外，我还添加了应用更改所需的方法。 acnhor 的变化是：-

anchor = OptionProperty('right',option=["right","left"])

方法的变化是：-

def set_pos_labels(self, widget):
    """Sets the position of the floating labels."""

    if self.anchor == "right":
        widget.x = Window.width - widget.width - dp(86)
    
    elif self.anchor == "left":
        widget.x = widget.width + dp(86)
    

def set_pos_root_button(self, instance):
    """Sets the position of the root button."""

    if self.anchor == "right":
        instance.y = dp(20)
        instance.x = Window.width - (dp(56) + dp(20))
        
    elif self.anchor == "left":
        instance.y = dp(20)
        instance.x = (dp(56) + dp(20))

def set_pos_bottom_buttons(self, instance):
    """Sets the position of the bottom buttons in a stack."""

    if self.anchor == "right":
        if self.state != "open":
            instance.y = instance.height / 2
        instance.x = Window.width - (instance.height + instance.width / 2)
        
    elif self.anchor == "left":
        if self.state != "open":
            instance.y = instance.height / 2
        instance.x = (instance.height + instance.width / 2)

我添加了左锚点属性，因为默认情况下存在右锚点。

我写的Builder字符串如下：-

MDFloatingActionButtonSpeedDial:
     data : app.data_download
     rotation_root_button : True
     id : download_button
     icon: 'download'
     anchor: 'left'
                    
                    
MDFloatingActionButtonSpeedDial:
      data : app.data_return
      rotation_root_button: True
      icon : 'arrow-left'
      anchor: 'right'

现在，每当我尝试将锚点属性设置为“左”而不是构建器字符串文件中的默认选项（右）时，程序都会返回错误。我想告知，如果我将锚点的默认值设置为左侧，则会收到将锚点设置为右侧的错误，而当我将锚点的默认值设置为右侧时，则会收到将锚点设置为左侧的错误。我收到的错误是：-

 Traceback (most recent call last):
 File "C:\Users\user\Anaconda3\lib\site-packages\kivy\lang\builder.py", line 700, in _apply_rule
 setattr(widget_set, key, value)
 File "kivy\weakproxy.pyx", line 35, in kivy.weakproxy.WeakProxy.__setattr__
 File "kivy\properties.pyx", line 497, in kivy.properties.Property.__set__
 File "kivy\properties.pyx", line 541, in kivy.properties.Property.set
 File "kivy\properties.pyx", line 532, in kivy.properties.Property.set
 File "kivy\properties.pyx", line 1252, in kivy.properties.OptionProperty.check
 ValueError: MDFloatingActionButtonSpeedDial.anchor is set to an invalid option 'left'. Must be one 
 of: []

 During handling of the above exception, another exception occurred:

 Traceback (most recent call last):
 File "onlinecv2.py", line 500, in <module>
 ScanIt().run()
 File "C:\Users\user\Anaconda3\lib\site-packages\kivy\app.py", line 829, in run
 root = self.build()
 File "onlinecv2.py", line 435, in build
 camerascreen    = Builder.load_string(screen_helper)
 File "C:\Users\user\Anaconda3\lib\site-packages\kivy\lang\builder.py", line 405, in load_string
 rule_children=rule_children)
 File "C:\Users\user\Anaconda3\lib\site-packages\kivy\lang\builder.py", line 707, in _apply_rule
 e), cause=tb)
 kivy.lang.builder.BuilderException: Parser: File "<inline>", line 154:
 ...
     152:                        id : download_button
     153:                        icon: 'download'
 >>  154:                        anchor: 'left'
     155:
     156:
 ...
 ValueError: MDFloatingActionButtonSpeedDial.anchor is set to an invalid option 'left'. Must be one 
 of: []
 File "C:\Users\user\Anaconda3\lib\site-packages\kivy\lang\builder.py", line 700, in _apply_rule
 setattr(widget_set, key, value)
 File "kivy\weakproxy.pyx", line 35, in kivy.weakproxy.WeakProxy.__setattr__
 File "kivy\properties.pyx", line 497, in kivy.properties.Property.__set__
 File "kivy\properties.pyx", line 541, in kivy.properties.Property.set
 File "kivy\properties.pyx", line 532, in kivy.properties.Property.set
 File "kivy\properties.pyx", line 1252, in kivy.properties.OptionProperty.check

当我没有在 kivy 文件中设置任何锚点值时，我得到的输出（这是不需要的）如下：-

因此，如果您能为我提供一个解决方案来解决此错误，以便我可以同时使用锚点属性“左”和“右”，我将很高兴。

Answer 1

当您在 OptionProperty 中使用多个选项时，应该使用

options

而不是

option

anchor = OptionProperty("right, options=("left", "right"))