ViewModel parent class

PrimeViewModel.cs

public class PrimeViewModel : INotifyPropertyChanged
{		
	protected bool SetProperty<T>(ref T backingStore, T value,
	[CallerMemberName] string propertyName = "",
	Action onChanged = null)
	{
		if (EqualityComparer<T>.Default.Equals(backingStore, value))
			return false;

		backingStore = value;
		onChanged?.Invoke();
		OnPropertyChanged(propertyName);
		return true;
	}


	public event PropertyChangedEventHandler PropertyChanged;
	protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
	{
		var changed = PropertyChanged;
		if (changed == null)
			return;

		changed.Invoke(this, new PropertyChangedEventArgs(propertyName));
	}
}