/// <summary>
/// The workhorse to expand a threaded listview item
/// </summary>
/// <param name="lvItem"></param>
/// <param name="activate">true, if lvItem should be activated</param>
internal void ExpandListViewItem(ThreadedListViewItem lvItem, bool activate)
{
int selIdxsCount = SelectedIndices.Count;
var selIdxs = new int[selIdxsCount];
SelectedIndices.CopyTo(selIdxs, 0);
ThreadedListViewItem[] newItems;
if (lvItem != null && lvItem.Collapsed)
{
if (RaiseBeforeExpandEventCancel(lvItem))
{
lvItem.StateImageIndex = 0; // switch to non-state image (no +/-)
return;
}
int paramItemIndex = lvItem.Index;
int currentIndent = lvItem.IndentLevel;
// if (base.SelectedItems.Count > 0 && activate)
// selectedItemIndex = paramItemIndex;
newItems = RaiseExpandEvent(lvItem);
if (newItems == null)
{
ThreadedListViewItem item = _noChildsPlaceHolder;
if (item == null)
{
item = new ThreadedListViewItemPlaceHolder(SR.FeedListNoChildsMessage)
{
Font = new Font(Font.FontFamily, Font.Size, FontStyle.Regular)
};
}
newItems = new[] { item };
}
if (newItems.Length > 1 && ListViewItemSorter != null)
{
// sort new child entries according to listview sortorder
Array.Sort(newItems, ListViewItemSorter);
}
if (_showInGroups)
{
APIEnableGrouping(false);
}
BeginUpdate();
try
{
lvItem.SetThreadState(true);
lock (Items)
{
foreach (var newListItem in newItems)
{
// check, if we have all subitems for correct grouping
while (newListItem.SubItems.Count < Columns.Count)
{
newListItem.SubItems.Add(String.Empty);
}
newListItem.Parent = lvItem;
Items.Insert(paramItemIndex + 1, newListItem);
newListItem.IndentLevel = currentIndent + 1;
paramItemIndex++;
}
}
}
finally
{
EndUpdate();
}
RedrawItems();
if (_showInGroups)
{
APIEnableGrouping(true);
}
// Make the last inserted subfolder visible, then the parent folder visible,
// per default treeview behavior.
try
{
EnsureVisible(paramItemIndex - 1);
EnsureVisible(lvItem.Index);
}
catch (Exception ex)
{
_log.Error("EnsureVisible() failed", ex);
}
if (activate)
{
SelectedItems.Clear();
lvItem.Selected = true;
lvItem.Focused = true;
}
else if (selIdxsCount > 0)
{
// foreach (int i in selIdxs) {
// this.Items[i].Selected = true;
// }
}
RaiseAfterExpandEvent(lvItem, newItems);
}
}
/// <summary>
/// Insert items as a replacement for a placeholder item inserted before.
/// The placeholder item will be identified by the placeHolderTicket to be provided.
/// </summary>
/// <param name="placeHolderTicket">The unique placeholder item's ticket. (string)</param>
/// <param name="newChildItems">ThreadedListViewItem array</param>
/// <param name="sortOnInsert">True uses the current sort column and order to insert childs.
/// Set to false, if you want to sort by your own.</param>
/// <exception cref="ArgumentNullException">If placeHolderTicket is null or empty</exception>
public void InsertItemsForPlaceHolder(string placeHolderTicket, ThreadedListViewItem[] newChildItems,
bool sortOnInsert)
{
if (string.IsNullOrEmpty(placeHolderTicket))
{
throw new ArgumentNullException("placeHolderTicket");
}
ThreadedListViewItemPlaceHolder placeHolder = null;
lock (Items)
{
for (int i = 0; i < Items.Count; i++)
{
var p = Items[i] as ThreadedListViewItemPlaceHolder;
if (p != null)
{
// found one; check ticket
if (p.InsertionPointTicket.Equals(placeHolderTicket))
{
placeHolder = p;
break;
}
}
}
// the ThreadedListViewItemPlaceHolder to work on is not anymore displayed;
// because of a refresh or user has collapsed the parent meanwhile
if (placeHolder == null)
{
return;
}
int parentItemIndex = placeHolder.Index;
int parentIndentLevel = placeHolder.IndentLevel;
try
{
BeginUpdate();
// remove the placeholder
Items.RemoveAt(parentItemIndex);
if (newChildItems == null || newChildItems.Length == 0)
{
ThreadedListViewItem item = _noChildsPlaceHolder;
if (item == null)
{
item = new ThreadedListViewItemPlaceHolder(SR.FeedListNoChildsMessage)
{
Font = new Font(Font.FontFamily, Font.Size, FontStyle.Regular)
};
}
newChildItems = new[] { item };
}
if (newChildItems.Length > 1 && _sorter.SortOrder != SortOrder.None && sortOnInsert)
{
// sort new child entries according to listview sortorder
Array.Sort(newChildItems, _sorter.GetComparer());
}
// now insert the new items
for (int i = 0; i < newChildItems.Length; i++)
{
ThreadedListViewItem newListItem = newChildItems[i];
newListItem.Parent = placeHolder.Parent;
// check, if we have all subitems for correct grouping
while (newListItem.SubItems.Count < Columns.Count)
{
newListItem.SubItems.Add(String.Empty);
}
if (parentItemIndex < Items.Count)
{
//_log.Info("InsertItemsForPlaceHolder() insert at " + String.Format("{0}", parentItemIndex + 1));
Items.Insert(parentItemIndex, newListItem);
}
else
{
//_log.Info("InsertItemsForPlaceHolder() append.");
Items.Add(newListItem);
}
newListItem.IndentLevel = parentIndentLevel;
// only valid after the item is part of the listview items collection!
parentItemIndex++;
} //iterator.MoveNext
}
finally
{
EndUpdate();
}
} //lock
UpdateItems();
}