// Toggle the sort order (ascending/descending) for the field selected in the sort fields list
private void ChangeFieldSortOrder(object sender, RoutedEventArgs e)
{
// Verify that there is a selected sort field in the list
OrderFieldOption selectedSortField = OrderByFieldsListBox.SelectedItem as OrderFieldOption;
if (selectedSortField == null)
{
return;
}
// Create a new order field info to define the sort for the selected field
OrderBy newOrderBy = new OrderBy(selectedSortField.OrderInfo.FieldName, selectedSortField.OrderInfo.SortOrder);
OrderFieldOption newSortDefinition = new OrderFieldOption(true, newOrderBy);
// Toggle the sort order from the current value
if (newSortDefinition.OrderInfo.SortOrder == SortOrder.Ascending)
{
newSortDefinition.OrderInfo.SortOrder = SortOrder.Descending;
}
else
{
newSortDefinition.OrderInfo.SortOrder = SortOrder.Ascending;
}
// Add the new OrderBy at the same location in the collection and remove the old one
_orderByFields.Insert(_orderByFields.IndexOf(selectedSortField), newSortDefinition);
_orderByFields.Remove(selectedSortField);
}
// Add the selected field in the "group by" list to the "order by" list
private void AddSortFieldClicked(object sender, RoutedEventArgs e)
{
// Verify that there is a selected field in the "group by" list
if (GroupFieldsListBox.SelectedItem == null)
{
return;
}
// Get the name of the selected field and ensure that it's in the list of selected group fields (checked on in the list, e.g.)
string selectedFieldName = GroupFieldsListBox.SelectedItem.ToString();
if (!_groupByFields.Contains(selectedFieldName))
{
ShowMessage("Only fields used for grouping can be used to order results.", "Order fields");
return;
}
// Verify that the field isn't already in the "order by" list
OrderFieldOption existingOrderBy = _orderByFields.FirstOrDefault(f => f.OrderInfo.FieldName == selectedFieldName);
if (existingOrderBy == null)
{
// Create a new OrderBy for this field and add it to the collection (default to ascending sort order)
OrderBy newOrderBy = new OrderBy(selectedFieldName, SortOrder.Ascending);
OrderFieldOption orderField = new OrderFieldOption(false, newOrderBy);
_orderByFields.Add(orderField);
}
}
// Remove the selected field from the list of "order by" fields
private void RemoveSortFieldClicked(object sender, RoutedEventArgs e)
{
// Verify that there is a selected item in the "order by" list
if (OrderByFieldsListBox.SelectedItem == null)
{
return;
}
// Get the selected OrderFieldOption object and remove it from the collection
OrderFieldOption selectedOrderBy = OrderByFieldsListBox.SelectedItem as OrderFieldOption;
_orderByFields.Remove(selectedOrderBy);
}
// Handle when the check box for a "group by" field is checked on or off by adding or removing the field from the collection
private void GroupFieldCheckChanged(object sender, RoutedEventArgs e)
{
// Get the check box that raised the event (group field)
CheckBox groupFieldCheckBox = (CheckBox)sender;
// Get the field name
string fieldName = groupFieldCheckBox.Content.ToString();
// See if the field is being added or removed from the "group by" list
bool fieldAdded = groupFieldCheckBox.IsChecked == true;
// See if the field already exists in the "group by" list
bool fieldIsInList = _groupByFields.Contains(fieldName);
// If the field is being added, and is NOT in the list, add it ...
if (fieldAdded && !fieldIsInList)
{
_groupByFields.Add(fieldName);
// Also add it to the "order by" list
OrderBy orderBy = new OrderBy(fieldName, SortOrder.Ascending);
OrderFieldOption orderOption = new OrderFieldOption(false, orderBy);
_orderByFields.Add(orderOption);
}
// If the field is being removed and it IS in the list, remove it ...
else if (!fieldAdded && fieldIsInList)
{
_groupByFields.Remove(fieldName);
// Also check for this field in the "order by" list and remove if necessary (only group fields can be used to order results)
OrderFieldOption orderBy = _orderByFields.FirstOrDefault(field => field.OrderInfo.FieldName == fieldName);
if (orderBy != null)
{
// Remove the field from the "order by" list
_orderByFields.Remove(orderBy);
}
}
}
