private T GetValueOrInheritedOrDefault <T>(StyledPropertyBase <T> property)
{
var o = this;
var inherits = property.Inherits;
var value = default(T);
while (o != null)
{
var values = o._values;
if (values?.TryGetValue(property, out value) == true)
{
return(value);
}
if (!inherits)
{
break;
}
o = o.InheritanceParent as AvaloniaObject;
}
return(property.GetDefaultValue(GetType()));
}
private T GetInheritedOrDefault <T>(StyledPropertyBase <T> property)
{
if (property.Inherits && InheritanceParent is AvaloniaObject o)
{
return(o.GetValueOrInheritedOrDefault(property));
}
return(property.GetDefaultValue(GetType()));
}
/// <summary>
/// Called for each inherited property when the <see cref="InheritanceParent"/> changes.
/// </summary>
/// <typeparam name="T">The type of the property value.</typeparam>
/// <param name="property">The property.</param>
/// <param name="oldParent">The old inheritance parent.</param>
internal void InheritanceParentChanged <T>(
StyledPropertyBase <T> property,
IAvaloniaObject oldParent)
{
var oldValue = oldParent switch
{
AvaloniaObject o => o.GetValueOrInheritedOrDefault(property),
null => property.GetDefaultValue(GetType()),
_ => oldParent.GetValue(property)
};
var newValue = GetInheritedOrDefault(property);
if (!EqualityComparer <T> .Default.Equals(oldValue, newValue))
{
RaisePropertyChanged(property, oldValue, newValue);
}
}
