Question

我必须通过后面的代码定义一个组合框：

var cmbLogin = new ComboBox()
{
    Width = 200,
    Height = m_dFontSize + 10,
    FontSize = m_dFontSize,
    Margin = new Thickness(20),
    BorderBrush = new SolidColorBrush(m_ExeCfg.GetForeground()),
    HorizontalContentAlignment = HorizontalAlignment.Center,
    Background = Brushes.Transparent,<--------------HERE
    Foreground = new SolidColorBrush(m_ExeCfg.GetForeground()),
    Focusable = true,
};

因此背景在win7中变得透明，但在win10中则不然。

我已经通过xaml看到了一些解决方案但是只能在代码后面应用它们。感谢名单

Answer 1

您无法简单地设置ComboBox的Background属性以更改其在Windows 8和10上的背景。您需要按照此处的建议定义自定义控件模板：https://blog.magnusmontin.net/2014/04/30/changing-the-background-colour-of-a-combobox-in-wpf-on-windows-8/。

将默认模板复制到XAML标记后，您可以设置＆＃34; templateRoot＆＃34;的背景属性。 ToggleButton样式中的边框元素为{TemplateBinding Background}

<ControlTemplate TargetType="{x:Type ToggleButton}">
                    <Border x:Name="templateRoot" BorderBrush="{StaticResource ComboBox.Static.Border}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" SnapsToDevicePixels="true">
...

然后，您必须将自定义样式应用于以编程方式创建的ComboBox：

var cmbLogin = new ComboBox()
{
    Width = 200,
    Height = m_dFontSize + 10,
    FontSize = m_dFontSize,
    Margin = new Thickness(20),
    BorderBrush = new SolidColorBrush(m_ExeCfg.GetForeground()),
    HorizontalContentAlignment = HorizontalAlignment.Center,
    Background = Brushes.Transparent,
    Foreground = new SolidColorBrush(m_ExeCfg.GetForeground()),
    Focusable = true,
    Style = Resources["ComboBoxStyle1"] as Style
};

如果你真的非常希望不使用任何XAML标记，你必须等到加载ComboBox，然后在可视树中找到Border元素并设置它的Background属性：

var cmbLogin = new ComboBox()
{
    Width = 200,
    Height = m_dFontSize + 10,
    FontSize = m_dFontSize,
    Margin = new Thickness(20),
    BorderBrush = new SolidColorBrush(m_ExeCfg.GetForeground()),
    HorizontalContentAlignment = HorizontalAlignment.Center,
    Foreground = new SolidColorBrush(m_ExeCfg.GetForeground()),
    Focusable = true,
};

cmbLogin.Loaded += (ss, ee) => 
{
    var toggleButton = cmb.Template.FindName("toggleButton", cmbLogin) as System.Windows.Controls.Primitives.ToggleButton;
    if(toggleButton != null)
    {
        Border border = toggleButton.Template.FindName("templateRoot", toggleButton) as Border;
        if (border != null)
            border.Background = Brushes.Transparent;
    }
};

WPF组合框透明背景不适用于Windows 10

1 个答案: