@Override
	public boolean doChanged(ObservableValue<? extends String> observable,
			String oldValue, String newValue) 
	{
		int i = 0;
		try
		{
			i = Integer.parseInt(newValue);
		}
		catch(NumberFormatException nfe)
		{
			label.setText("Must be an integer");
			return false;
		}
		
		if(!acceptNegative && i < 0)
		{
			if(label != null)label.setText("Cannot be negative");
			return false;
		}
		if(!acceptPositive && i > 0)
		{
			if(label != null)label.setText("Cannot be positive");
			return false;
		}
		
		return true;
	}