/// <summary>
/// Notifies this object that a related <see cref="IPropertyStore"/> has changed.
/// </summary>
/// <param name="changed">Changed object instance.</param>
/// <param name="change">Change details.</param>
public virtual void NotifyChange(IPropertyStore changed, PropertyStoreChangeEventArgs change)
{
lock (SyncRoot)
{
// Suspend events
SuspendEvents();
try
{
// Notify subclass
OnChangeNotification(changed, change);
}
finally
{
// Resume events
ResumeEvents();
}
}
}
/// <summary>
/// Fires the <see cref="PropertyStoreChanged"/> and <see cref="PropertyChanged"/> events.
/// </summary>
protected virtual void OnPropertyChanged(PropertyStoreChangeEventArgs change)
{
// Validate
if (change == null)
{
throw new ArgumentNullException(nameof(change));
}
// Fire events
PropertyStoreChanged?.Invoke(this, change);
if (PropertyChanged != null)
{
foreach (var propertyId in change.Keys)
{
var propertyName = _propertyNames[propertyId];
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
/// <summary>
/// Called when events are resumed the last time, i.e. is not fired when nested. Fires the <see cref="PropertyStoreChanged"/> event when changes are pending.
/// </summary>
protected override void OnEventsResumed()
{
lock (SyncRoot)
{
// Fire pending PropertyChanged event
if (_changedProperties.Count > 0)
{
// Build event
var args = new PropertyStoreChangeEventArgs(_changedProperties.ToArray());
// Clear cache
_changedProperties.Clear();
// Fire events
OnPropertyChanged(args);
}
// Call base class method
base.OnEventsResumed();
}
}
/// <summary>
/// Called when the <see cref="IPropertyStore.PropertyStoreChanged"/> event is fired on any of the <see cref="Children"/>.
/// </summary>
/// <param name="sender">Event initiator.</param>
/// <param name="arguments">Event arguments.</param>
/// <remarks>Inheritors must call this base class method first.</remarks>
public virtual void OnChildPropertyChanged(object sender, PropertyStoreChangeEventArgs arguments)
{
// Currently empty but still required to call for future base code support
}
/// <summary>
/// Handles change notification events, when this object is notified that a related view object has changed via the <see cref="NotifyChange"/> method.
/// </summary>
/// <remarks>
/// Thread safe locking, <see cref="EventCache.SuspendEvents"/> and <see cref="EventCache.ResumeEvents"/> are handled by the caller. The base class
/// implementation does nothing.
/// </remarks>
/// <param name="changed">Changed view object instance.</param>
/// <param name="change">Change details.</param>
protected virtual void OnChangeNotification(IPropertyStore changed, PropertyStoreChangeEventArgs change)
{
}
