两个列值的数据触发器比较
本文关键字:数据 触发器 比较 两个 | 更新日期: 2023-09-27 18:11:17
我试图根据同一行中两个单元格的比较值设置DataTrigger
。我的困难是单元格不是(也不可能是)同一项的属性。网格是在代码隐藏中生成的。
public class EqualityConverter : IValueConverter
{
public object Convert(object values, Type targetType, object parameter, CultureInfo culture)
{
string currentValue = values.ToString();
string compareToValue = Column[2].Item.Value.ToString(); //This clearly doesn't work, but it's the intent I'm after.
if (currentValue.Equals(compareToValue))
return false;
return true;
}
XAML(Binding Path=Value)
效果很好。(ConverterParameter = Column2.Value)
是我的问题所在。有什么建议,我可以检索这个吗??
<DataTrigger Binding="{Binding Path=Value, Converter={StaticResource EqualityConverter}}" Value="True">
<Setter Property="Background" Value="Yellow" />
</DataTrigger>
我不能绑定到项目属性的原因是单元格值本身就是一个项目:所以我试图比较Column2的"值"属性。
public class GenericProperty : INotifyPropertyChanged
{
public GenericProperty(string name, object value)
{
Name = name;
Value = value;
}
public string Name { get; private set; }
public object Value { get; set; }
每个DataGridCell
中的DataContext
为该DataGridRow
中显示的记录(项)。因此,您所要做的就是比较第二个Column
中显示的属性值。
<DataTrigger Binding="{Binding secondColumnProp}" value="True">
<Setter Property="Background" Value="Yellow"/>
</DataTrigger>
UPDATE # 1后用户评论
您必须使用DataGridCell
的Loaded
事件,因为到那时绑定将被评估。
<DataGrid.CellStyle>
<Style TargetType="DataGridCell">
<EventSetter Event="Loaded" Handler="DataGridCell_Loaded"/>
</Style>
</DataGrid.CellStyle>
void DataGridCell_Loaded(object sender, RoutedEventArgs e)
{
DataGridCell cell = sender as DataGridCell;
DependencyObject reference = cell;
while (reference.GetType() != typeof(DataGridRow))
reference = VisualTreeHelper.GetParent(reference);
DataGridRow row = reference as DataGridRow;
while (reference.GetType() != typeof(DataGrid))
reference = VisualTreeHelper.GetParent(reference);
DataGrid grid = reference as DataGrid;
FrameworkElement elem = grid.Columns[2].GetCellContent(row);
// use elem.DataContext, or traverse elem's visualtree to do something
// code below is just an example
if (elem is TextBlock)
{
System.Diagnostics.Debug.WriteLine((elem as TextBlock).Text);
if ((elem as TextBlock).Text == "34")
cell.Background = Brushes.DarkMagenta;
}
}
在努力寻找一个更简单、更直接的解决方案之后……最后,我为对象添加了一个属性,用作占位符来标识匹配的值:
public GenericProperty(string name, object value, string match)
{
Name = name;
Value = value;
** Match = match; **
}
public string Name { get; private set; }
public object Value { get; set; }
public string Match { get; set; }
然后我有一个方法,循环遍历我的Collection,并为匹配我的"column 2"项的项设置新属性的值为"true":
private void IdentifyMatchingItems(ObservableCollection<GenericObject> groupedCollection)
{
foreach (var collectionObject in groupedCollection)
{
int x = collectionObject.Properties.Count;
int propertyCount = x - 1;
string masterValue = collectionObject.Properties[2].Value.ToString();
// string ObjectNotNull = collectionObject.Properties[propertyNumber].Value.ToString();
for (int i = 2; i <= propertyCount; i++)
{
if (collectionObject.Properties[i].Value.Equals(masterValue))
{
collectionObject.Properties[i].Latest = "yes";
}
}
}
}
最后,我有一个基于"Match"属性的dataGrid单元格样式的数据触发器。