改變DatGrid ScrollBar在鼠標上的可見性？

Question

如何在DataGrid的IsMouseOver屬性上切換DataGrid滾動條的可見性？ 我想使滾動條可見，當鼠標懸停在DataGrid和看不見的，當鼠標離開DataGrid的。 XAML示例將不勝感激。

Answer 1

我會申請一種新的風格，如下所示：

<Style x:Key="dataGridStyle" TargetType={x:Type DataGrid}> 
    <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Hidden"/> 
    <Style.Triggers> 
     <Trigger Property="IsMouseOver" Value="True"> 
      <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/> 
     </Trigger> 
    </Style.Triggers> 
</Style> 

Answer 2

創建一個值轉換器：

[ValueConversion(typeof(bool), typeof(ScrollBarVisibility))] 
sealed class MouseOverToScrollBarVisibility : IValueConverter 
{ 
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) 
    { 
     return ((bool)value) ? ScrollBarVisibility.Auto : ScrollBarVisibility.Hidden; 
    } 

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

某處聲明它的資源：

<Window.Resources> 
    <local:MouseOverToScrollBarVisibility x:Key="MouseOverToScrollBarVisibility" /> 
</Window.Resources> 

並用它來綁定ScrollViewer.VerticalScrollBarVisibility財產IsMouseOver屬性：

<DataGrid ScrollViewer.VerticalScrollBarVisibility= 
      "{Binding IsMouseOver, 
        RelativeSource={RelativeSource Self}, 
        Converter={StaticResource MouseOverToScrollBarVisibility}}"> 
</DataGrid>