private void MoveItemDown(object obj)
{
if (selectedIndex == -1)
{
return;
}
lock (this)
{
Debug.Assert(selectedIndex >= 0, "SelectedIndex must be valid, not -1, for moving.");
Debug.Assert(
selectedIndex < (Highlighters.Count - 1),
"SelectedIndex must be a value less than the max index of the collection.");
Debug.Assert(
Highlighters.Count > 1,
"Can only move an item if there are more than one items in the collection.");
var oldIndex = selectedIndex;
SelectedIndex = -1;
lock (Highlighters)
{
Highlighters.Swap(oldIndex, oldIndex + 1);
}
SelectedIndex = oldIndex + 1;
}
}
private void MoveItemUp(object obj)
{
if (selectedIndex != -1)
{
lock (this)
{
Debug.Assert(selectedIndex >= 0, "SelectedIndex must be valid, e.g not -1.");
Debug.Assert(
Highlighters.Count > 1, "Can not move item unless more than one item in the collection.");
int oldIndex = selectedIndex;
SelectedIndex = -1;
lock (Highlighters)
{
Highlighters.Swap(oldIndex, oldIndex - 1);
}
SelectedIndex = oldIndex - 1;
}
}
}