/// <summary>
/// Filter attached property to attach the DataGridFilterHost instance to the owning DataGrid.
/// This property is only used by code and is not accessible from XAML.
/// </summary>
/// <param name="dataGrid">The data grid.</param>
/// <returns>The <see cref="DataGridFilterHost"/></returns>
public static DataGridFilterHost GetFilter(this DataGrid dataGrid)
{
if (dataGrid.GetValue(FilterProperty) is not DataGridFilterHost value)
{
value = new DataGridFilterHost(dataGrid);
dataGrid.SetValue(FilterProperty, value);
}
return(value);
}
public static DataGridFilterHost GetFilter([NotNull] this DataGrid dataGrid)
{
var value = (DataGridFilterHost)dataGrid.GetValue(FilterProperty);
if (value == null)
{
value = new DataGridFilterHost(dataGrid);
dataGrid.SetValue(FilterProperty, value);
}
return(value);
}
public static DataGridFilterHost GetFilter([NotNull] this DataGrid dataGrid)
{
Contract.Requires(dataGrid != null);
Contract.Ensures(Contract.Result <DataGridFilterHost>() != null);
var value = (DataGridFilterHost)dataGrid.GetValue(FilterProperty);
if (value == null)
{
value = new DataGridFilterHost(dataGrid);
dataGrid.SetValue(FilterProperty, value);
}
return(value);
}
private void self_Loaded(object sender, RoutedEventArgs e)
{
if (FilterHost == null)
{
// Find the ancestor column header and data grid controls.
ColumnHeader = this.FindAncestorOrSelf<DataGridColumnHeader>();
if (ColumnHeader == null)
throw new InvalidOperationException("DataGridFilterColumnControl must be a child element of a DataGridColumnHeader.");
DataGrid = ColumnHeader.FindAncestorOrSelf<DataGrid>();
if (DataGrid == null)
throw new InvalidOperationException("DataGridColumnHeader must be a child element of a DataGrid");
// Find our host and attach ourself.
FilterHost = DataGrid.GetFilter();
}
FilterHost.AddColumn(this);
DataGrid.SourceUpdated += DataGrid_SourceOrTargetUpdated;
DataGrid.TargetUpdated += DataGrid_SourceOrTargetUpdated;
DataGrid.RowEditEnding += DataGrid_RowEditEnding;
// Must set a non-null empty template here, else we won't get the coerce value callback when the columns attached property is null!
Template = _emptyControlTemplate;
// Bind our IsFilterVisible and Template properties to the corresponding properties attached to the
// DataGridColumnHeader.Column property. Use binding instead of simple assignment since columnHeader.Column is still null at this point.
var isFilterVisiblePropertyPath = new PropertyPath("Column.(0)", DataGridFilterColumn.IsFilterVisibleProperty);
BindingOperations.SetBinding(this, VisibilityProperty, new Binding() { Path = isFilterVisiblePropertyPath, Source = ColumnHeader, Mode = BindingMode.OneWay, Converter = _booleanToVisibilityConverter });
var templatePropertyPath = new PropertyPath("Column.(0)", DataGridFilterColumn.TemplateProperty);
BindingOperations.SetBinding(this, TemplateProperty, new Binding() { Path = templatePropertyPath, Source = ColumnHeader, Mode = BindingMode.OneWay });
var filterPropertyPath = new PropertyPath("Column.(0)", DataGridFilterColumn.FilterProperty);
BindingOperations.SetBinding(this, FilterProperty, new Binding() { Path = filterPropertyPath, Source = ColumnHeader, Mode = BindingMode.TwoWay });
}
