public void TestMeasure(double availableWidth, double availableHeight)
        {
            var view     = new Mock <IStepper>();
            var drawable = new StepperDrawable(view.Object);
            var size     = drawable.Measure(availableWidth, availableHeight);

            Assert.Equal(new Size(DeviceInfo.ScalingFactor, DeviceInfo.ScalingFactor), size);
        }