public void LoadExpansionState(ITreeViewModelItem treeViewModelItem)
{
var isExpanded = ItemStates.SingleOrDefault(o => o.Item.IsAlive && o.Item.Target.Equals(treeViewModelItem.Value))?.
GetExpansionState(treeViewModelItem.GetAncestors().Select(o => o.Value));
if (isExpanded != null)
{
treeViewModelItem.IsExpanded = (bool)isExpanded;
}
}
public void SaveExpansionState(ITreeViewModelItem treeViewModelItem)
{
var currentStates = ItemStates.SingleOrDefault(o => o.Item.IsAlive && o.Item.Target.Equals(treeViewModelItem.Value));
if (currentStates != null)
{
currentStates.SetExpansionState(treeViewModelItem.GetAncestors().Select(o => o.Value), treeViewModelItem.IsExpanded);
}
else
{
var stateRetainer = new ReferenceExpansionRetainer(treeViewModelItem.Value);
stateRetainer.SetExpansionState(treeViewModelItem.GetAncestors().Select(o => o.Value), treeViewModelItem.IsExpanded);
ItemStates.Add(stateRetainer);
}
}