public void drawInBackground(Canvas canvas) {
        Axis axis = chart.getChartData().getAxisYLeft();
        if (null != axis) {
            prepareAxisToDraw(axis, LEFT);
            drawAxisLines(canvas, axis, LEFT);
        }

        axis = chart.getChartData().getAxisYRight();
        if (null != axis) {
            prepareAxisToDraw(axis, RIGHT);
            drawAxisLines(canvas, axis, RIGHT);
        }

        axis = chart.getChartData().getAxisXBottom();
        if (null != axis) {
            prepareAxisToDraw(axis, BOTTOM);
            drawAxisLines(canvas, axis, BOTTOM);
        }

        axis = chart.getChartData().getAxisXTop();
        if (null != axis) {
            prepareAxisToDraw(axis, TOP);
            drawAxisLines(canvas, axis, TOP);
        }
    }
Prepare axes coordinates and draw axes lines(if enabled) in the background.

@param canvas
hellocharts-library/src/lecho/lib/hellocharts/renderer/AxesRenderer.java