private void CreateNativeGroupListeners()
{
foreach (var visualStateGroup in EnumerateVisualStateGroups())
{
VisualGroupListener groupListener = null;
foreach (VisualState visualState in visualStateGroup.States)
{
var stateListeners = FindListenerCollection(visualState.Name);
if (stateListeners == null)
{
continue;
}
if (groupListener == null)
{
groupListener = new VisualGroupListener();
}
groupListener.AddStateListenersCollection(stateListeners);
}
if (groupListener == null)
{
continue;
}
_visualStateGroupObservers.Add(new VisualStateGroupObserver(visualStateGroup, groupListener));
}
}
public VisualStateGroupObserver(VisualStateGroup visualGroup, VisualGroupListener groupListener) : base(groupListener)
{
_visualGroup = visualGroup;
_visualStates = new HashSet <string>(visualGroup.States.Cast <VisualState>().Select(s => s.Name), StringComparer.OrdinalIgnoreCase);
_visualGroup.CurrentStateChanged += VisualGroupOnCurrentStateChanged;
Update();
}
private void CreateGroupObservers()
{
var implementationRoot = ImplementationRoot;
if (implementationRoot == null)
{
return;
}
var advisor = implementationRoot as IVisualStateManagerAdvisor;
var visualStateGroups = advisor != null ? advisor.VisualStateGroups : VisualStateManager.GetInstance(implementationRoot)?.Groups;
if (visualStateGroups == null)
{
return;
}
foreach (var stateGroup in visualStateGroups)
{
if (FindGroupObserver(stateGroup.Name) != null)
{
continue;
}
var visualGroupListener = new VisualGroupListener();
foreach (var visualState in stateGroup.States)
{
var listeners = FindListenerCollection(visualState.Name) ?? new VisualStateListenerCollection(visualState.Name);
// Template changed. Keep previous visual states.
if (listeners.IsActive)
{
visualGroupListener.GoToState(listeners.StateName, false);
}
visualGroupListener.AddStateListenersCollection(listeners);
}
_visualStateGroupObservers.Add(new DelegateVisualStateGroupObserver(stateGroup.Name, stateGroup.States.Select(v => v.Name), visualGroupListener));
}
}
private VisualStateListenerCollection GetListenerCollection(string name, bool create)
{
var listenerCollection = FindListenerCollection(name);
if (listenerCollection == null && create == false)
{
return(null);
}
var groupObserver = FindGroupObserverByStateName(name);
if (groupObserver != null)
{
listenerCollection = groupObserver.GroupListener.GetListenerCollection(name, create);
}
if (listenerCollection != null)
{
_stateListenerCollections.Add(listenerCollection);
return(listenerCollection);
}
listenerCollection = new VisualStateListenerCollection(name);
_stateListenerCollections.Add(listenerCollection);
var visualStateGroup = EnumerateVisualStateGroups().SingleOrDefault(g => g.States.Cast <VisualState>().Any(s => string.Equals(s.Name, name, StringComparison.OrdinalIgnoreCase)));
if (visualStateGroup == null)
{
return(listenerCollection);
}
var groupListener = new VisualGroupListener();
groupListener.AddStateListenersCollection(listenerCollection);
groupObserver = new VisualStateGroupObserver(visualStateGroup, groupListener);
_visualStateGroupObservers.Add(groupObserver);
return(listenerCollection);
}
protected VisualStateGroupObserverBase(VisualGroupListener groupListener)
{
GroupListener = groupListener;
}
public DelegateVisualStateGroupObserver(string groupName, IEnumerable <string> states, VisualGroupListener groupListener) : base(groupListener)
{
_states = states.ToList();
Name = groupName;
}