void PanelEvent(
object sender,
System.ComponentModel.PropertyChangedEventArgs e)
{
Debug.Assert( sender is Autodesk.Windows.RibbonTab,
"expected sender to be a ribbon tab" );
if( e.PropertyName == "Title" )
{
ICollection<ElementId> ids = _uiapp
.ActiveUIDocument.Selection.GetElementIds();
int n = ids.Count;
string s = ( 0 == n )
? "<nil>"
: string.Join( ", ",
ids.Select<ElementId, string>(
id => id.IntegerValue.ToString() ) );
Debug.Print(
"CmdSelectionChanged: selection changed: "
+ s );
}
}