A DESCRIPTION OF THE PROBLEM :
if our code have this line "setHorizontalZeroLineVisible(false);"
the HorizontalZeroLine will be visible,
but if our code have this line "setHorizontalZeroLineVisible(true);"
the HorizontalZeroLine will be invisible.
Obviously,the actual situation is opposite to the expected situation.
And,I found that the class "XYChart" in package "javafx.scene.chart" hava these lines:

                if ((y!=yAxisZero || !isHorizontalZeroLineVisible()) && y >= 0 && y < yAxisHeight) {
                    horizontalGridLines.getElements().add(new MoveTo(left,top+y+0.5));
                    horizontalGridLines.getElements().add(new LineTo(left+xAxisWidth,top+y+0.5));
                }

I think it should be replaced with these codes:

                if ((y!=yAxisZero || isHorizontalZeroLineVisible()) && y >= 0 && y < yAxisHeight) {
                    horizontalGridLines.getElements().add(new MoveTo(left,top+y+0.5));
                    horizontalGridLines.getElements().add(new LineTo(left+xAxisWidth,top+y+0.5));
                }



FREQUENCY : always