使用轉換器設置WPF單元格樣式

Question

我有兩個WPF單元格樣式，我想基於轉換器應用它們。 我是我的示例下面我試圖改變背景顏色（在實際應用程序中，我會改變比這更多，但這不是問題的關鍵，所以我只是簡化）。

<Style TargetType="{x:Type DataGridCell}" x:Key="WinCellStyle"> 
    <Setter Property="Template"> 
     <Setter.Value> 
      <ControlTemplate TargetType="{x:Type DataGridCell}"> 
       <Border x:Name="border" 
         Background="LightGreen" 
         BorderBrush="Transparent" 
         BorderThickness="1" 
         SnapsToDevicePixels="True"> 

        <ContentPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" /> 
       </Border> 
      </ControlTemplate> 
     </Setter.Value> 
    </Setter> 
</Style> 

<Style TargetType="{x:Type DataGridCell}" x:Key="LossCellStyle"> 
    <Setter Property="Template"> 
     <Setter.Value> 
      <ControlTemplate TargetType="{x:Type DataGridCell}"> 
       <Border x:Name="border" 
         Background="LightSalmon" 
         BorderBrush="Transparent" 
         BorderThickness="1" 
         SnapsToDevicePixels="True"> 

        <ContentPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" /> 
       </Border> 
      </ControlTemplate> 
     </Setter.Value> 
    </Setter> 
</Style> 

然後我有一個轉換器：

public class AmountToCellStyleConverter : IValueConverter 
{ 
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) 
    { 

     var valueAsDecimal = (decimal?) value; 
     if (valueAsDecimal > 0) 
     { 
      return Application.Current.FindResource("WinCellStyle") as Style; 
     } 
     return Application.Current.FindResource("LossCellStyle") as Style; 
    } 

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) 
    { 
     throw new NotImplementedException(); 
    }  
} 

怎樣然後在單元格樣式調用呢？

XAML：

<Window.Resources> 
    <converter:AmountToCellStyleConverter x:Key="AmountToCellStyleConverter"/>  
</Window.Resources> 

... 

<DataGridTextColumn CellStyle="{Binding ??? What goes here}" Binding="{Binding Path=MarketBookSelection.TotalWagerStakeWin, StringFormat=N2}" Header="Stake Win" Width="Auto" /> 

也許答案是，這是不可能的，我需要去了一些其他的途徑？

Answer 1

綁定不的DataGridColumn的CellStyle工作，因此嘗試創建爲TextBox目標類型，而不是DataGridCell樣式和寫DataGridTemplateColumn這樣的：

<DataGrid.Resources> 
    <local:AmountToCellStyleConverter x:Key="StyleConverter" /> 
</DataGrid.Resources> 

... 

<DataGridTemplateColumn Width="1.5*" 
         Header="SimpleHeader" 
         IsReadOnly="False"> 

    <DataGridTemplateColumn.CellTemplate> 
     <DataTemplate>       
      <TextBox Style="{Binding Path=NumberValue, Converter={StaticResource StyleConverter}}" 
        Text="{Binding Path=NumberValue}" />        
     </DataTemplate> 
    </DataGridTemplateColumn.CellTemplate> 
</DataGridTemplateColumn> 

還是比寫一個值，而不是2，在這種情況下類型的轉換器的輸入值將是String：

<DataGridTemplateColumn.CellTemplate> 
    <DataTemplate>       
     <TextBox Style="{Binding Path=Text, 
           RelativeSource={RelativeSource Mode=Self}, 
           Converter={StaticResource StyleConverter}}" 
       Text="{Binding Path=NumberValue}" />        
    </DataTemplate> 
</DataGridTemplateColumn.CellTemplate> 

樣式爲TextBox位於App.xaml：

<Application.Resources> 
    <Style x:Key="WinCellStyle" TargetType="{x:Type TextBox}"> 
     <Setter Property="SnapsToDevicePixels" Value="True" /> 

     <Setter Property="Template"> 
      <Setter.Value> 
       <ControlTemplate TargetType="{x:Type TextBoxBase}"> 
        <Border Background="LightGreen" 
          BorderThickness="1"> 

         <ScrollViewer x:Name="PART_ContentHost" 
             SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" /> 
        </Border> 
       </ControlTemplate> 
      </Setter.Value> 
     </Setter> 
    </Style> 

    <Style x:Key="LossCellStyle" TargetType="{x:Type TextBox}"> 
     <Setter Property="SnapsToDevicePixels" Value="True" /> 

     <Setter Property="Template"> 
      <Setter.Value> 
       <ControlTemplate TargetType="{x:Type TextBox}"> 
        <Border Background="LightSalmon" 
          BorderThickness="1"> 

         <ScrollViewer x:Name="PART_ContentHost" 
             SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" /> 
        </Border> 
       </ControlTemplate> 
      </Setter.Value> 
     </Setter> 
    </Style> 
</Application.Resources> 

Converter看起來是這樣的：

public class AmountToCellStyleConverter : IValueConverter 
{ 
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture) 
    { 
     var valueAsDecimal = (int)value; 

     if (valueAsDecimal > 0) 
     { 
      return Application.Current.FindResource("WinCellStyle") as Style; 
     } 

     return Application.Current.FindResource("LossCellStyle") as Style; 
    } 

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) 
    { 
     throw new NotImplementedException(); 
    } 
} 

或者，你可以這樣做：改變轉換器的邏輯返回True或False並在CellStyle，你可以這樣寫：

<DataGridTextColumn Header="SimpleHeader"          
        Width="1.5*" 
        Binding="{Binding Path=NumberValue}"> 

    <DataGridTextColumn.CellStyle> 
     <Style TargetType="{x:Type DataGridCell}"> 
      <Style.Triggers> 
       <DataTrigger Binding="{Binding Path=NumberValue, Converter={StaticResource MyConverter}}" Value="True"> 
        <Setter Property="Background" Value="Yellow" /> 
        <Setter Property="BorderThickness" Value="1" /> 
       </DataTrigger> 

       <DataTrigger Binding="{Binding Path=NumberValue, Converter={StaticResource MyConverter}}" Value="False"> 
        <Setter Property="Background" Value="Red" /> 
        <Setter Property="BorderThickness" Value="1" /> 
       </DataTrigger> 
      </Style.Triggers> 
     </Style> 
    </DataGridTextColumn.CellStyle> 
</DataGridTextColumn>