我在 .Net MAUI 中设置单选按钮样式时遇到了一些问题。最初,我注意到 Windows 和 Android 上的单选按钮外观并不一致,如下图所示:
它们不仅不同,而且用于设置按钮样式的可用选项也很有限。定义颜色的唯一选项是“BorderColor”、“BackgroundColor”和“TextColor”。 “BorderColor”和“BackgroundColor”对单选按钮本身的颜色完全没有影响。我想更改实际单选按钮的颜色。
所以我决定创建一个控件模板来帮助我。这是我的控件模板:
<ControlTemplate x:Key="RadioButtonTemplate">
<Border Stroke="Transparent" BackgroundColor="Transparent">
<VisualStateManager.VisualStateGroups>
<VisualStateGroupList>
<VisualStateGroup x:Name="CheckedStates">
<VisualState x:Name="Checked">
<VisualState.Setters>
<Setter TargetName="check" Property="Opacity" Value="1" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="Unchecked">
<VisualState.Setters>
<Setter TargetName="check" Property="Opacity" Value="0" />
</VisualState.Setters>
</VisualState>
</VisualStateGroup>
</VisualStateGroupList>
</VisualStateManager.VisualStateGroups>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="20" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<Grid WidthRequest="20" HeightRequest="20" Grid.Column="0" VerticalOptions="Center" HorizontalOptions="Center">
<Ellipse x:Name="border_circle" StrokeThickness="2" Stroke="DarkBlue" Fill="White" WidthRequest="18" HeightRequest="18" HorizontalOptions="Center" VerticalOptions="Center" />
<Ellipse x:Name="check" Fill="DarkBlue" WidthRequest="10" HeightRequest="10" HorizontalOptions="Center" VerticalOptions="Center" />
</Grid>
<ContentPresenter Margin="10,0,0,0" Grid.Column="1" HorizontalOptions="Start" VerticalOptions="Center" />
</Grid>
</Border>
</ControlTemplate>
<Style TargetType="RadioButton" x:Key="RadioButtonStyle">
<Setter Property="ControlTemplate" Value="{StaticResource RadioButtonTemplate}" />
</Style>
效果相当好,所以现在我在 Android 和 Windows 上获得了以下外观:
现在我还有最后一个问题。当我使用默认的单选按钮(没有我的控制模板)时,只要我将IsEnabled
设置为
false
,它们就会可靠地变成“浅灰色”颜色。我想这样做,以便我可以禁用我的单选按钮并将其变成浅灰色(以表明它已禁用),同时仍然使用我的控件模板,这样我就有了统一的外观和感觉。因此我尝试向我的控件模板添加
Disabled
视觉状态,但它似乎不起作用。这是我的新控件模板,具有
Disabled
状态:
<ControlTemplate x:Key="RadioButtonTemplate">
<Border Stroke="Transparent" BackgroundColor="Transparent">
<VisualStateManager.VisualStateGroups>
<VisualStateGroupList>
<VisualStateGroup x:Name="CheckedStates">
<VisualState x:Name="Checked">
<VisualState.Setters>
<Setter TargetName="check" Property="Opacity" Value="1" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="Unchecked">
<VisualState.Setters>
<Setter TargetName="check" Property="Opacity" Value="0" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="Disabled">
<VisualState.Setters>
<Setter TargetName="border_circle" Property="Stroke" Value="LightGray" />
<Setter TargetName="check" Property="Fill" Value="LightGray" />
</VisualState.Setters>
</VisualState>
</VisualStateGroup>
</VisualStateGroupList>
</VisualStateManager.VisualStateGroups>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="20" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<Grid WidthRequest="20" HeightRequest="20" Grid.Column="0" VerticalOptions="Center" HorizontalOptions="Center">
<Ellipse x:Name="border_circle" StrokeThickness="2" Stroke="DarkBlue" Fill="White" WidthRequest="18" HeightRequest="18" HorizontalOptions="Center" VerticalOptions="Center" />
<Ellipse x:Name="check" Fill="DarkBlue" WidthRequest="10" HeightRequest="10" HorizontalOptions="Center" VerticalOptions="Center" />
</Grid>
<ContentPresenter Margin="10,0,0,0" Grid.Column="1" HorizontalOptions="Start" VerticalOptions="Center" />
</Grid>
</Border>
</ControlTemplate>
<Style TargetType="RadioButton" x:Key="RadioButtonStyle">
<Setter Property="ControlTemplate" Value="{StaticResource RadioButtonTemplate}" />
</Style>
不幸的是,它不起作用。当单选按钮被禁用时,不仅颜色不会改变,而且我的第二个设置器(设置“检查”对象的“填充”属性)也会导致编译时错误(“无法解析边框类型上的属性填充”) ”)。有什么建议吗?
<ControlTemplate x:Key="RadioButtonTemplate">
<Border Stroke="Transparent" BackgroundColor="Transparent">
<VisualStateManager.VisualStateGroups>
<VisualStateGroupList>
<VisualStateGroup x:Name="CheckedStates">
<VisualState x:Name="Checked">
<VisualState.Setters>
<Setter TargetName="check" Property="Opacity" Value="1" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="Unchecked">
<VisualState.Setters>
<Setter TargetName="check" Property="Opacity" Value="0" />
</VisualState.Setters>
</VisualState>
</VisualStateGroup>
</VisualStateGroupList>
</VisualStateManager.VisualStateGroups>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="20" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<Grid WidthRequest="20" HeightRequest="20" Grid.Column="0" VerticalOptions="Center" HorizontalOptions="Center">
<Ellipse x:Name="border_circle" StrokeThickness="2" Stroke="{TemplateBinding BorderColor}" Fill="White" WidthRequest="18" HeightRequest="18" HorizontalOptions="Center" VerticalOptions="Center" />
<Ellipse x:Name="check" Fill="{TemplateBinding BorderColor}" WidthRequest="10" HeightRequest="10" HorizontalOptions="Center" VerticalOptions="Center" />
</Grid>
<ContentPresenter Margin="10,0,0,0" Grid.Column="1" HorizontalOptions="Start" VerticalOptions="Center" />
</Grid>
</Border>
</ControlTemplate>
<Style TargetType="RadioButton" x:Key="RadioButtonStyle">
<Setter Property="ControlTemplate" Value="{StaticResource RadioButtonTemplate}" />
<Style.Triggers>
<Trigger TargetType="RadioButton" Property="IsEnabled" Value="False">
<Setter Property="BorderColor" Value="LightGray" />
</Trigger>
<Trigger TargetType="RadioButton" Property="IsEnabled" Value="True">
<Setter Property="BorderColor" Value="DarkBlue" />
</Trigger>
</Style.Triggers>
</Style>
VisualState.Setters
前缀中添加属性,例如要设置的元素的
Opacity
,例如
Ellipse
:
<VisualState x:Name="Checked">
<VisualState.Setters>
<Setter TargetName="border_circle" Property="Ellipse.Stroke" Value="{TemplateBinding BorderColor}" />
<Setter TargetName="check" Property="Ellipse.Opacity" Value="1" />
</VisualState.Setters>
</VisualState>