问题描述
我有3列，而使用特定的转换器时，我成功地将中间和右列的可见性更改为可见性崩溃或可见。
我的问题是，当这些列应该可见时，我希望它们的宽度以星为单位，而折叠宽度必须为自动时。
然后，如果可见，则我所有的列都共享相等的空间，否则她将占用所有空间，并可以将其居中放置在父对象中。
我设置了可见性转换器
internal class TradeUnitLevelToVisibilityConverter : BaseConverter,IValueConverter
{
public object Convert(object value,Type targettype,object parameter,System.Globalization.CultureInfo culture)
{
return value != null && (TradeUnit)value == TradeUnit.Unit
? Visibility.Collapsed
: Visibility.Visible;
}
public object ConvertBack(object value,System.Globalization.CultureInfo culture)
{
return null;
}
}
我的宽度转换器
public object Convert(object value,System.Globalization.CultureInfo culture)
{
return value != null && (TradeUnit)value == TradeUnit.Unit
? new GridLength(0,GridUnitType.Auto)
: new GridLength(5,GridUnitType.Star);
}
public object ConvertBack(object value,System.Globalization.CultureInfo culture)
{
return null;
}
}
我的xaml：
<Grid Grid.Column="1" Background="{StaticResource Black3C3D41Brush}">
<Grid Grid.Column="1" HorizontalAlignment="Stretch">
<Grid.ColumnDeFinitions>
<ColumnDeFinition Width="0.5*"/>
<ColumnDeFinition Width="2.5*"/>
<ColumnDeFinition >
<!--<ColumnDeFinition.Style>
<Style targettype="ColumnDeFinition">
<Setter Property="Width" Value="*"/>
<Style.Triggers>
<DataTrigger Binding="{Binding,Converter={eshopeur:TradeUnitLevelToVisibilityConverter}}" Value="Unit">
<Setter Property="Width" Value="auto"/>
</DataTrigger>
</Style.Triggers>
</Style>
</ColumnDeFinition.Style>-->
</ColumnDeFinition>
<ColumnDeFinition >
<!--<ColumnDeFinition.Style>
<Style targettype="ColumnDeFinition">
<Setter Property="Width" Value="2.5*"/>
<Style.Triggers>
<DataTrigger Binding="{Binding,Converter={eshopeur:TradeUnitLevelToVisibilityConverter}}" Value="Collapsed">
<Setter Property="Width" Value="auto"/>
</DataTrigger>
</Style.Triggers>
</Style>
</ColumnDeFinition.Style>-->
</ColumnDeFinition>
<ColumnDeFinition Width="0.5*"/>
</Grid.ColumnDeFinitions>
<Grid Grid.Column="1" HorizontalAlignment="Center">
...
</Grid>
<Grid Grid.Column="2" Visibility="{Binding UnitTradeUnitlevel,Converter={eshopeur:TradeUnitLevelToVisibilityConverter}}"
HorizontalAlignment="Stretch"
Width="{Binding UnitTradeUnitlevel,Converter={auxilaryscreen:UnitTradeUnitToVisibilityConverter}}" >
<Grid>
...
</Grid>
<Grid Grid.Column="3" HorizontalAlignment="Stretch"
Width="{Binding UnitTradeUnitlevel,Converter={auxilaryscreen:UnitTradeUnitToVisibilityConverter}}"
Visibility="{Binding UnitTradeUnitlevel,Converter={eshopeur:TradeUnitLevelToVisibilityConverter}}">
...
</Grid>
</Grid>
</Grid>
我尝试使用触发器，但是我不知道如何正确设置它们，因为他们正在检查可见性转换器以适应宽度。
这是我期望的 而所有可见的
崩溃时
我的实际结果是崩溃：
您有什么解决方案可以同时更改列的可见性和宽度？
解决方法
获得结果的一种方法是为列定义创建附加行为。
附加行为是具有3个附加属性的静态类。您可以更改名称以使其真正有意义。
- DefaultWidth-列定义的默认宽度
- UnitWidth-当
TradeUnit为Unit时列定义的宽度 - TradeUnit-贸易单位
TradeUnit发生更改时，该行为会将列定义的Width设置为正确的值DefaultWidth或UnitWidth。
using System.Windows;
using System.Windows.Controls;
namespace SO
{
public static class TradeUnitColumnWidthBehavior
{
#region DefaultWidth (Attached Property)
public static readonly DependencyProperty DefaultWidthProperty =
DependencyProperty.RegisterAttached(
"DefaultWidth",typeof(GridLength),typeof(TradeUnitColumnWidthBehavior),new PropertyMetadata(null));
public static GridLength GetDefaultWidth(DependencyObject obj)
{
return (GridLength)obj.GetValue(DefaultWidthProperty);
}
public static void SetDefaultWidth(DependencyObject obj,GridLength value)
{
obj.SetValue(DefaultWidthProperty,value);
}
#endregion
#region UnitWidth (Attached Property)
public static readonly DependencyProperty UnitWidthProperty =
DependencyProperty.RegisterAttached(
"UnitWidth",new PropertyMetadata(null));
public static GridLength GetUnitWidth(DependencyObject obj)
{
return (GridLength)obj.GetValue(UnitWidthProperty);
}
public static void SetUnitWidth(DependencyObject obj,GridLength value)
{
obj.SetValue(UnitWidthProperty,value);
}
#endregion
#region TradeUnit (Attached Property)
public static readonly DependencyProperty TradeUnitProperty =
DependencyProperty.RegisterAttached(
"TradeUnit",typeof(MainWindowViewModel.TradeUnit),new PropertyMetadata(MainWindowViewModel.TradeUnit.None,OnTradeUnitChanged));
public static MainWindowViewModel.TradeUnit GetTradeUnit(DependencyObject obj)
{
return (MainWindowViewModel.TradeUnit)obj.GetValue(TradeUnitProperty);
}
public static void SetTradeUnit(DependencyObject obj,MainWindowViewModel.TradeUnit value)
{
obj.SetValue(TradeUnitProperty,value);
}
private static void OnTradeUnitChanged(DependencyObject d,DependencyPropertyChangedEventArgs e)
{
var columnDefinition = (ColumnDefinition)d;
if (columnDefinition == null) return;
if ((MainWindowViewModel.TradeUnit) e.NewValue == MainWindowViewModel.TradeUnit.Unit)
{
columnDefinition.Width = GetUnitWidth(d);
}
else
{
columnDefinition.Width = GetDefaultWidth(d);
}
}
#endregion
}
}
以下是XAML的示例：
<Grid ShowGridLines="True">
<!-- -->
<Grid.ColumnDefinitions>
<ColumnDefinition Width="0.5*" />
<ColumnDefinition Width="2.5*"
local:TradeUnitColumnWidthBehavior.DefaultWidth="2.5*"
local:TradeUnitColumnWidthBehavior.TradeUnit="{Binding RelativeSource={RelativeSource AncestorType={x:Type Grid}},Path=DataContext.UnitTradeUnitLevel}"
local:TradeUnitColumnWidthBehavior.UnitWidth="*" />
<ColumnDefinition Width="1.5*"
local:TradeUnitColumnWidthBehavior.DefaultWidth="1.5*"
local:TradeUnitColumnWidthBehavior.TradeUnit="{Binding RelativeSource={RelativeSource AncestorType={x:Type Grid}},Path=DataContext.UnitTradeUnitLevel}"
local:TradeUnitColumnWidthBehavior.UnitWidth="Auto" />
<ColumnDefinition Width="2.5*"
local:TradeUnitColumnWidthBehavior.DefaultWidth="2.5*"
local:TradeUnitColumnWidthBehavior.TradeUnit="{Binding RelativeSource={RelativeSource AncestorType={x:Type Grid}},Path=DataContext.UnitTradeUnitLevel}"
local:TradeUnitColumnWidthBehavior.UnitWidth="Auto" />
<ColumnDefinition Width="0.5*" />
</Grid.ColumnDefinitions>
<Border x:Name="Border1"
Grid.Column="1"
Background="Red">
<Button
HorizontalAlignment="Center"
VerticalAlignment="Center"
Command="{Binding TradeUnitCommand}"
Content="Change Unit" />
</Border>
<Border
Grid.Column="2"
Background="Green"
Visibility="{Binding UnitTradeUnitLevel,Converter={StaticResource TradeUnitLevelToVisibilityConverter}}" />
<Border
Grid.Column="3"
Background="Blue"
Visibility="{Binding UnitTradeUnitLevel,Converter={StaticResource TradeUnitLevelToVisibilityConverter}}" />
</Grid>
最后我改变了我的xaml树和一个转换器：当一列可见时，另一列不可见，全部设置为width = auto。
这似乎可以完成工作，如果我可以找到更清洁的解决方案，那就太好了。如果有人已经用触发器完成了它，我就会对此感兴趣。