绑定样式名称并更改样式 VIA View Model

Question

如何更改元素 VIA 视图模型的样式，就像我想在单击按钮时切换样式一样。

XAML

<Grid x:Name="LayoutRoot"
      DataContext="{Binding Source={StaticResource IndexVMDataSource}}">
  <Button Content="Button"
          HorizontalAlignment="Left"
          Height="42"
          Margin="10,49,0,0"
          VerticalAlignment="Top"
          Width="130"
          Command="{Binding OnCommandName, Mode=OneWay}" />
  <HyperlinkButton Content="HyperlinkButton"
                   HorizontalAlignment="Left"
                   Height="34"
                   Margin="10,10,0,0"
                   VerticalAlignment="Top"
                   Width="216"
                   Style="{Binding QStyle}" />
</Grid>

虚拟机

private string _styleA = "HyperLink-Navi-Container";
private string _styleB = "HyperLink-Navi-Container-2";

private string qStyle;
public string QStyle
{
     get
     {
           return qStyle;
     }
     set
     {
          if (qStyle != value)
          {
               qStyle = value;
               NotifyPropertyChanged(Utility.GetPropertyName(() => QStyle));
          }
     }
}

private ICommand onCommandName = null;
public ICommand OnCommandName
{
     get
     {
         return onCommandName;
     }
     private set
     {
         onCommandName = value;
     }
}

public void Command()
{
     if (QStyle != _styleA)
         QStyle = _styleA;
     else if (QStyle != _styleB)
         QStyle = _styleB;            
}

Answer 1

您的QStyle 属性必须是Style 类型：

private Style qStyle;
public Style QStyle
{
    get { return qStyle; }
    set
    {
        if (qStyle != value)
        {
             qStyle = value;
             NotifyPropertyChanged(Utility.GetPropertyName(() => QStyle));
        }
    }
}

或者您在样式绑定中使用binding converter，它会为给定的字符串（例如样式资源的键）返回适当的Style：

<HyperlinkButton ...
    Style="{Binding QStyle, Converter={StaticResource YourStringToStyleConverter}}" />

---

由于您没有显示您定义样式的位置，我猜它们在您的用户控件的Resources 中。然后，您可以通过以下方式获取它们：

Style style = Resources["HyperLink-Navi-Container"] as Style;

如果资源是在 App.xaml 中定义的，您可以编写

Style style = Application.Current.Resources["HyperLink-Navi-Container"] as Style;