/// <summary>
/// Attaches the collection of behaviors to the specified <see cref="Windows.UI.Xaml.DependencyObject"/>.
/// </summary>
/// <param name="associatedObject">The <see cref="Windows.UI.Xaml.DependencyObject"/> to which to attach.</param>
/// <exception cref="InvalidOperationException">The <see cref="BehaviorCollection"/> is already attached to a different <see cref="Windows.UI.Xaml.DependencyObject"/>.</exception>
public void Attach(DependencyObject associatedObject)
{
if (associatedObject == this.AssociatedObject)
{
return;
}
if (Windows.ApplicationModel.DesignMode.DesignModeEnabled)
{
return;
}
if (this.AssociatedObject != null)
{
throw new InvalidOperationException(ResourceHelper.GetString("CannotAttachBehaviorMultipleTimesExceptionMessage"));
}
Debug.Assert(associatedObject != null, "The previous checks should keep us from ever setting null here.");
this.AssociatedObject = associatedObject;
foreach (DependencyObject item in this)
{
IBehavior behavior = (IBehavior)item;
behavior.Attach(this.AssociatedObject);
}
}
private IBehavior VerifiedAttach(DependencyObject item)
{
IBehavior behavior = item as IBehavior;
if (behavior == null)
{
throw new InvalidOperationException("NonBehaviorAddedToBehaviorCollectionExceptionMessage");
}
if (this.oldCollection.Contains(behavior))
{
throw new InvalidOperationException("DuplicateBehaviorInCollectionExceptionMessage");
}
if (this.AssociatedObject != null)
{
behavior.Attach(this.AssociatedObject);
}
return(behavior);
}
/// <summary>
/// Attaches the collection of behaviors to the specified <see cref="IAvaloniaObject"/>.
/// </summary>
/// <param name="associatedObject">The <see cref="IAvaloniaObject"/> to which to attach.</param>
/// <exception cref="InvalidOperationException">The <see cref="BehaviorCollection"/> is already attached to a different <see cref="IAvaloniaObject"/>.</exception>
public void Attach(IAvaloniaObject?associatedObject)
{
if (associatedObject == AssociatedObject)
{
return;
}
if (AssociatedObject != null)
{
throw new InvalidOperationException("An instance of a behavior cannot be attached to more than one object at a time.");
}
Debug.Assert(associatedObject != null, "The previous checks should keep us from ever setting null here.");
AssociatedObject = associatedObject;
foreach (var item in this)
{
IBehavior behavior = (IBehavior)item;
behavior.Attach(AssociatedObject);
}
}
private IBehavior VerifiedAttach(AvaloniaObject item)
{
IBehavior behavior = item as IBehavior;
if (behavior == null)
{
throw new InvalidOperationException("Only IBehavior types are supported in a BehaviorCollection.");
}
if (oldCollection.Contains(behavior))
{
throw new InvalidOperationException("Cannot add an instance of a behavior to a BehaviorCollection more than once.");
}
if (AssociatedObject != null)
{
behavior.Attach(AssociatedObject);
}
return(behavior);
}
