protected void Set <T>(ref T field, T value, Action <T> changeHandler, [CallerMemberName] string propertyName = null) where T : IEquatable <T>
{
var oldValue = field;
if (PropertyChanged.TryUpdate(this, ref field, value, propertyName))
{
changeHandler?.Invoke(oldValue);
}
}
/// <summary>
/// Utility function to make writing property updates easier.
/// If the backing field's value does not match the new value, the backing field is updated and PropertyChanged gets called.
/// </summary>
/// <typeparam name="T">The type of the property being updated.</typeparam>
/// <param name="backingField">A reference to the backing field of the property being changed.</param>
/// <param name="newValue">The new value for the property.</param>
/// <param name="propertyName">The name of the property to notify on. If the property is the caller, the compiler will figure this parameter out automatically.</param>
/// <returns>false if the data did not need to be updated, true if it did.</returns>
protected bool TryUpdate <T>(ref T backingField, T newValue, [CallerMemberName] string propertyName = null) where T : IEquatable <T>
{
return(PropertyChanged.TryUpdate(this, ref backingField, newValue, propertyName));
}