AchartEngine bug in addFillOutsideLine()

gistfile1.txt

package com.example.achartengineexample;
import android.graphics.Color;
import android.os.Bundle;
import android.widget.LinearLayout;
import androidx.appcompat.app.AppCompatActivity;
import org.achartengine.ChartFactory;
import org.achartengine.GraphicalView;
import org.achartengine.chart.PointStyle;
import org.achartengine.model.XYMultipleSeriesDataset;
import org.achartengine.model.XYSeries;
import org.achartengine.renderer.XYMultipleSeriesRenderer;
import org.achartengine.renderer.XYSeriesRenderer;

public class MainActivity extends AppCompatActivity {

    private GraphicalView mChart;
    private XYMultipleSeriesDataset mDataset = new XYMultipleSeriesDataset();
    private XYMultipleSeriesRenderer mRenderer = new XYMultipleSeriesRenderer();
    private XYSeries mCurrentSeries;
    private XYSeries mHorizon;
    private XYSeriesRenderer mCurrentRenderer;
    private XYSeriesRenderer mHorizonRenderer;

    private void initChart() {
        mCurrentSeries = new XYSeries("Sample Data");
        mHorizon = new XYSeries("Horizon");
        mDataset.addSeries(mCurrentSeries);
        mDataset.addSeries(mHorizon);
        mCurrentRenderer = new XYSeriesRenderer();
        mCurrentRenderer.setPointStyle(PointStyle.CIRCLE);
        mCurrentRenderer.setFillPoints(true);
        mRenderer.addSeriesRenderer(mCurrentRenderer);
        mHorizonRenderer = new XYSeriesRenderer();
        mHorizonRenderer.setColor(Color.GRAY);
        mRenderer.addSeriesRenderer(mHorizonRenderer);
        XYSeriesRenderer.FillOutsideLine fill = new XYSeriesRenderer.FillOutsideLine(XYSeriesRenderer.FillOutsideLine.Type.BOUNDS_BELOW);
        int transparentRed = Color.argb(0.10F, 1.0F, 0.0F, 0.0F);
        fill.setColor(transparentRed);
        mCurrentRenderer.addFillOutsideLine(fill);
    }

    private void addSampleData() {
        mHorizon.add(1, 0);
        mHorizon.add(7, 0);
        mCurrentSeries.add(1, 2);
        mCurrentSeries.add(2, 3);
        mCurrentSeries.add(3, 2);
        mCurrentSeries.add(4, -5);
        mCurrentSeries.add(5, 4);
        mCurrentSeries.add(6, -3);
        mCurrentSeries.add(7, 5);
    }

    LinearLayout layout;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        layout = new LinearLayout(this);
        LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(900, 600);
        layout.setLayoutParams(layoutParams);
        setContentView(layout);
    }

    protected void onResume() {
        super.onResume();

        if (mChart == null) {
            initChart();
            addSampleData();
            mChart = ChartFactory.getCubeLineChartView(this, mDataset, mRenderer, 0.3f);
            layout.addView(mChart);
        } else {
            mChart.repaint();
        }
    }

}