Unblock row editing on WPF DataGrid - wpf

Question

I have validation in DataGrid. I am copying and trying to paste multiple rows. But if there is a validation error in one of the rows on insertion, the validation will will be called in and disable editing of the other rows, therefore next rows will not be inserted.
My ValidationRule:
public class MyValidationRule : ValidationRule
{
public override ValidationResult Validate(object value, System.Globalization.CultureInfo cultureInfo)
{
MyModel myModel = (value as BindingGroup).Items[0] as MyModel ;
if (myModel.Top > myModel.Bottom)
{
return new ValidationResult(false, "Error!");
}
return new ValidationResult(true,null);
}
}
XAML:
<DataGrid.RowValidationRules>
<MyValidationRule ValidationStep="UpdatedValue"/>
<DataGrid.RowValidationRules>
The paste code:
protected virtual void OnExecutedPaste(object target, ExecutedRoutedEventArgs args)
{
if (ExecutePasteEvent != null)
{
ExecutePasteEvent(target, args);
if (args.Handled)
{
return;
}
}
List<string[]> clipboardData = Clipboard
Helper2.ParseClipboardData();
int minRowIndex = Items.Count;
int maxRowIndex = Items.Count;
int minColumn = 0;
if (SelectedCells.Any())
{
minRowIndex = SelectedCells.Min(g=> Items.IndexOf(g.Item));
maxRowIndex = Items.Count;
minColumn = SelectedCells.Min(g=> g.Column.DisplayIndex);
}
int minColumnDisplayIndex = (SelectionUnit != DataGridSelectionUnit.FullRow) ? minColumn : 0;
int maxColumnDisplayIndex = Columns.Count - 1;
int rowDataIndex = 0;
List<Tuple<int, int>> cellsToSelect = new List<Tuple<int, int>>();
for (int i = minRowIndex; i <= maxRowIndex && rowDataIndex < clipboardData.Count; i++, rowDataIndex++)
{
if (i == maxRowIndex)
{
if (!CanUserPasteToNewRows)
continue;
ICollectionView cv = CollectionViewSource.GetDefaultView(Items);
IEditableCollectionView iecv = cv as IEditableCollectionView;
if (iecv != null)
{
if (minRowIndex + clipboardData.Count > Items.Count)
{
iecv.AddNew();
if (rowDataIndex < clipboardData.Count)
{
maxRowIndex = Items.Count;
}
}
}
}
if (i < Items.Count)
{
CurrentItem = Items[i];
BeginEditCommand.Execute(null, this);
int clipboardColumnIndex = 0;
for (int j = minColumnDisplayIndex; clipboardColumnIndex < clipboardData[rowDataIndex].Length; j++, clipboardColumnIndex++)
{
DataGridColumn column = null;
foreach (DataGridColumn columnIter in this.Columns)
{
if (columnIter.DisplayIndex == j)
{
column = columnIter;
break;
}
}
column?.OnPastingCellClipboardContent(Items[i], clipboardData[rowDataIndex][clipboardColumnIndex]);
cellsToSelect.Add(new Tuple<int, int>(i, j));
}
CommitEditCommand.Execute(this, this);
}
}
UnselectAll();
UnselectAllCells();
if (Items.Count < 1)
return;
CurrentItem = Items[minRowIndex];
if (SelectionUnit == DataGridSelectionUnit.FullRow)
{
SelectedItem = Items[minRowIndex];
}
else if (SelectionUnit == DataGridSelectionUnit.CellOrRowHeader || SelectionUnit == DataGridSelectionUnit.Cell)
{
foreach(var c in cellsToSelect)
{
if(Columns.Count < c.Item1 && Columns.Count < c.Item2)
SelectedCells.Add(new DataGridCellInfo(Items[c.Item1], Columns[c.Item2]));
}
}
}
And ClipboardHelper.ParseClipboardData(); will return a list of strings for example: {"row1", "value1", "value2"},{"row2", "value1", "value2"}.
How to paste all copied rows?
And I need to allow editing of all rows with errors, and not the last one.