StrokeStyle of FastLineRenderableSeries setting not working. (with Alpha Value)

I applied alpha color to FastLineRenderableSeries, but it was not visible. On the other hand, FastColumnRenderableSeries works well with alpha color. Please check the issue.

Example Code

class AlphaChart {
    private val colorAlpha00 = ColorUtil.argb(0x00, 0xFF, 0xCC, 0x80) // 0%
    private val colorAlpha1A = ColorUtil.argb(0x1A, 0xFF, 0xCC, 0x80) // 10%
    private val colorAlpha33 = ColorUtil.argb(0x33, 0xFF, 0xCC, 0x80) // 20%
    private val colorAlpha4D = ColorUtil.argb(0x4D, 0xFF, 0xCC, 0x80) // 30%
    private val colorAlpha66 = ColorUtil.argb(0x66, 0xFF, 0xCC, 0x80) // 40%
    private val colorAlpha80 = ColorUtil.argb(0x80, 0xFF, 0xCC, 0x80) // 50%
    private val colorAlpha99 = ColorUtil.argb(0x99, 0xFF, 0xCC, 0x80) // 60%
    private val colorAlphaB3 = ColorUtil.argb(0xB3, 0xFF, 0xCC, 0x80) // 70%
    private val colorAlphaCC = ColorUtil.argb(0xCC, 0xFF, 0xCC, 0x80) // 80%
    private val colorAlphaE6 = ColorUtil.argb(0xE6, 0xFF, 0xCC, 0x80) // 90%
    private val colorAlphaFF = ColorUtil.argb(0xFF, 0xFF, 0xCC, 0x80) // 100%

    fun initAlphaChart(surface: SciChartSurface) {
        surface.suspendUpdates {
            theme = R.style.SciChart_Alpha

            xAxes {
                numericAxis {
                    autoRange = AutoRange.Always
                    growBy = DoubleRange(0.1, 0.1)
                }
            }
            yAxes {
                numericAxis {
                    autoRange = AutoRange.Always
                    growBy = DoubleRange(0.2, 0.2)
                }
            }
            renderableSeries {
                fastColumnRenderableSeries {
                    dataSeries = createDataSeries(2.0)
                    paletteProvider = AlphaPaletteProvider()
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(3.0)
                    strokeStyle = SolidPenStyle(colorAlpha00, 2f) // 0% - Not Visible
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(3.1)
                    strokeStyle = SolidPenStyle(colorAlpha1A, 2f) // 10% - Not Visible
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(3.2)
                    strokeStyle = SolidPenStyle(colorAlpha33, 2f) // 20% - Not Visible
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(3.3)
                    strokeStyle = SolidPenStyle(colorAlpha4D, 2f) // 30% - Not Visible
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(3.4)
                    strokeStyle = SolidPenStyle(colorAlpha66, 2f) // 40% - Not Visible
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(3.5)
                    strokeStyle = SolidPenStyle(colorAlpha80, 2f) // 50% - Not Visible
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(3.6)
                    strokeStyle = SolidPenStyle(colorAlpha99, 2f) // 60% - Not Visible
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(3.7)
                    strokeStyle = SolidPenStyle(colorAlphaB3, 2f) // 70%
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(3.8)
                    strokeStyle = SolidPenStyle(colorAlphaCC, 2f) // 80%
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(3.9)
                    strokeStyle = SolidPenStyle(colorAlphaE6, 2f) // 90%
                }
                fastLineRenderableSeries {
                    dataSeries = createDataSeries(4.0)
                    strokeStyle = SolidPenStyle(colorAlphaFF, 2f) // 100%
                }
            }
            chartModifiers {
                rolloverModifier {}
            }
        }
    }

    private fun createDataSeries(yValues: Double): XyDataSeries<Int, Double> {
        return XyDataSeries<Int, Double>().apply {
            for (index in 1..10) {
                append(index, yValues)
            }
        }
    }
}


class AlphaPaletteProvider :
    PaletteProviderBase<FastColumnRenderableSeries>(FastColumnRenderableSeries::class.java),
    IFillPaletteProvider, IStrokePaletteProvider {
    private val colorAlpha00 = ColorUtil.argb(0x00, 0xFF, 0xCC, 0x80) // 0%
    private val colorAlpha1A = ColorUtil.argb(0x1A, 0xFF, 0xCC, 0x80) // 10%
    private val colorAlpha33 = ColorUtil.argb(0x33, 0xFF, 0xCC, 0x80) // 20%
    private val colorAlpha4D = ColorUtil.argb(0x4D, 0xFF, 0xCC, 0x80) // 30%
    private val colorAlpha66 = ColorUtil.argb(0x66, 0xFF, 0xCC, 0x80) // 40%
    private val colorAlpha80 = ColorUtil.argb(0x80, 0xFF, 0xCC, 0x80) // 50%
    private val colorAlpha99 = ColorUtil.argb(0x99, 0xFF, 0xCC, 0x80) // 60%
    private val colorAlphaB3 = ColorUtil.argb(0xB3, 0xFF, 0xCC, 0x80) // 70%
    private val colorAlphaCC = ColorUtil.argb(0xCC, 0xFF, 0xCC, 0x80) // 80%
    private val colorAlphaE6 = ColorUtil.argb(0xE6, 0xFF, 0xCC, 0x80) // 90%
    private val colorAlphaFF = ColorUtil.argb(0xFF, 0xFF, 0xCC, 0x80) // 100%

    private val colors = IntegerValues(
        intArrayOf(
            colorAlpha00,
            colorAlpha1A,
            colorAlpha33,
            colorAlpha4D,
            colorAlpha66,
            colorAlpha80,
            colorAlpha99,
            colorAlphaB3,
            colorAlphaCC,
            colorAlphaE6,
            colorAlphaFF
        )
    )

    override fun update() {}

    override fun getFillColors(): IntegerValues = colors

    override fun getStrokeColors(): IntegerValues = colors
}