private void RemoveCondition(object sender, FilterConditionUserControl condition)
 {
     FilterConditions.Remove(condition);
     LayoutPanel.Controls.Remove(condition);
 }
 private void AddCondition(FilterConditionUserControl condition)
 {
     condition.Removing        += RemoveCondition;
     condition.PropertyChanged += ChangeControlProperty;
     FilterConditions.Add(condition);
 }