@Override
    public void onChartViewportChanged() {
        if (isViewportCalculationEnabled) {
            calculateMaxViewport();
            computator.setMaxViewport(tempMaximumViewport);
            computator.setCurrentViewport(computator.getMaximumViewport());
        }
    }
Renderer for line chart. Can draw lines, cubic lines, filled area chart and scattered chart.
hellocharts-library/src/lecho/lib/hellocharts/renderer/LineChartRenderer.java