For a NumberAxis in a LineChart, calling: forceZeroInRangeProperty().set(false) doesn' t work when all the values on the Axis are negative. The zero line is still displayed, forcing the chart to be pushed down, so the chart details are not shown.

A test application to demonstrate the problem:

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.chart.LineChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart;
import javafx.stage.Stage;


public class AreaChartSample extends Application {

@Override public void start(Stage stage) {
        stage.setTitle("Line Chart - negative Y Axis");
        final NumberAxis xAxis = new NumberAxis(1, 31, 1);
        final NumberAxis yAxis = new NumberAxis();
        final LineChart<Number,Number> ac =
            new LineChart<Number,Number>(xAxis,yAxis);
        ac.setTitle("Test : Line chart - Zero line is shown ");
        
        yAxis.forceZeroInRangeProperty().set(false);
 
        XYChart.Series<Number, Number> seriesTest= new XYChart.Series<Number,Number>();
        seriesTest.getData().add(new XYChart.Data<Number,Number>(1, -1400));
        seriesTest.getData().add(new XYChart.Data<Number,Number>(3, -1410));
        seriesTest.getData().add(new XYChart.Data<Number,Number>(6, -1415));
        seriesTest.getData().add(new XYChart.Data<Number,Number>(9, -1478));
        seriesTest.getData().add(new XYChart.Data<Number,Number>(12, -1405));
        seriesTest.getData().add(new XYChart.Data<Number,Number>(15, -1438));
        seriesTest.getData().add(new XYChart.Data<Number,Number>(18, -1415));
        seriesTest.getData().add(new XYChart.Data<Number,Number>(21, -1413));
        seriesTest.getData().add(new XYChart.Data<Number,Number>(24, -1449));
        seriesTest.getData().add(new XYChart.Data<Number,Number>(27, -1421));
        seriesTest.getData().add(new XYChart.Data<Number,Number>(30, -1422));
        
        
        Scene scene = new Scene(ac,800,600);
        ac.getData().add(seriesTest);
        stage.setScene(scene);
        stage.show();
    }
 
    public static void main(String[] args) {
        launch(args);
    }

}