/// <remark>
/// OnPrivateSharedSizeScopePropertyChanged is called when new scope enters or
/// existing scope just left. In both cases if the DefinitionBase object is already registered
/// in SharedSizeState, it should un-register and register itself in a new one.
/// </remark>
private static void OnPrivateSharedSizeScopePropertyChanged(AvaloniaObject d, AvaloniaPropertyChangedEventArgs e)
{
DefinitionBase definition = (DefinitionBase)d;
if (definition.Parent != null)
{
SharedSizeScope privateSharedSizeScope = (SharedSizeScope)e.NewValue;
if (definition._sharedState != null)
{
// if definition is already registered And shared size scope is changing,
// then un-register the definition from the current shared size state object.
definition._sharedState.RemoveMember(definition);
definition._sharedState = null;
}
if ((definition._sharedState == null) && (privateSharedSizeScope != null))
{
string sharedSizeGroup = definition.SharedSizeGroup;
if (sharedSizeGroup != null)
{
// if definition is not registered and both: shared size group id AND private shared scope
// are available, then register definition.
definition._sharedState = privateSharedSizeScope.EnsureSharedState(definition.SharedSizeGroup);
definition._sharedState.AddMember(definition);
}
}
}
}
/// <summary>
/// <see cref="PropertyMetadata.PropertyChangedCallback"/>
/// </summary>
private static void OnSharedSizeGroupPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
DefinitionBase definition = (DefinitionBase)d;
if (definition.InParentLogicalTree)
{
string sharedSizeGroupId = (string)e.NewValue;
if (definition._sharedState != null)
{
// if definition is already registered AND shared size group id is changing,
// then un-register the definition from the current shared size state object.
definition._sharedState.RemoveMember(definition);
definition._sharedState = null;
}
if ((definition._sharedState == null) && (sharedSizeGroupId != null))
{
SharedSizeScope privateSharedSizeScope = definition.PrivateSharedSizeScope;
if (privateSharedSizeScope != null)
{
// if definition is not registered and both: shared size group id AND private shared scope
// are available, then register definition.
definition._sharedState = privateSharedSizeScope.EnsureSharedState(sharedSizeGroupId);
definition._sharedState.AddMember(definition);
}
}
}
}
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
#region Internal Methods
/// <summary>
/// Callback to notify about entering model tree.
/// </summary>
internal void OnEnterParentTree()
{
if (_sharedState == null)
{
// start with getting SharedSizeGroup value.
// this property is NOT inhereted which should result in better overall perf.
string sharedSizeGroupId = SharedSizeGroup;
if (sharedSizeGroupId != null)
{
SharedSizeScope privateSharedSizeScope = PrivateSharedSizeScope;
if (privateSharedSizeScope != null)
{
_sharedState = privateSharedSizeScope.EnsureSharedState(sharedSizeGroupId);
_sharedState.AddMember(this);
}
}
}
}