MPAndroidChart StackedBarChart显示值但没有条形

我开始使用MPAndroidChart库来构建一个StackedBarChart显示三个y值.这是代码:

public class Plot
{
    final Context context;
    final BarData data;

    private int count;

    public StackedBarPlot(Context context)
    {
        this.context = context;
        data = setData();
    }

    protected BarData setData()
    {
        final List entries = new ArrayList<>();
        for (DatabaseEntry entry : entryList)
        {
            final float total = (float) entry.getTotal();
            final float[] y = {100 * entry.getN1() / total,
                    100 * entry.getN2() / total, 100 * entry.getN3() / total};
            entries.add(new BarEntry(/*long*/entry.getDate(), y));
        }
        count = entries.size();


        final BarDataSet dataset = new BarDataSet(entries, null);
        dataset.setColors(new int[]{R.color.green, R.color.blue, R.color.red}, context);
        dataset.setStackLabels(labels);
        dataset.setDrawValues(true);
        dataset.setVisible(true);

        final BarData data = new BarData(dataset);
        data.setBarWidth(0.9f);
        return data;
    }

    public BarChart getChart(int id, View view)
    {
        final BarChart chart = (BarChart) view.findViewById(id);   

        chart.getAxisRight().setEnabled(false);
        chart.getAxisLeft().setEnabled(false);
        final Legend legend = chart.getLegend();
        legend.setDrawInside(true);
        legend.setVerticalAlignment(Legend.LegendVerticalAlignment.TOP);
        legend.setHorizontalAlignment(Legend.LegendHorizontalAlignment.CENTER);

        final XAxis xAxis = chart.getXAxis();
        xAxis.setValueFormatter(dateFormatter);
        xAxis.setPosition(XAxis.XAxisPosition.BOTTOM);
        xAxis.setDrawGridLines(false);
        xAxis.setLabelCount(count);

        chart.getDescription().setEnabled(false);
        chart.setData(data);
        chart.setFitBars(true);
        chart.invalidate();
        return chart;
    }

    private final IAxisValueFormatter dateFormatter = new IAxisValueFormatter()
    {
        @Override
        public String getFormattedValue(float value, AxisBase axis)
        {
            return new DateTime((long) value).toString(context.getString("E, MMM d"));
        }
    };
}

然后在我Fragment,我打电话:

public class MyFragment extends Fragment
{
    private Plot plot;

    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        plot = new Plot(getActivity());
    }

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup parent, Bundle savedInstanceState)
    {
        final View view = inflater.inflate(R.layout.fragment, parent, false);
        plot.getChart(R.id.chart, view);
        return view;
    }
}

并在MainActivity.java中

getFragmentManager().beginTransaction().replace(R.id.content, fragment).commit();

main_activity.xml

fragment.xml之

问题是条形图无法正确渲染.我可以看到值,但条形图没有显示.有什么建议？

这不像一些以前的帖子所建议的那样在库中出错.可能你只是误解了每个条的宽度是如何确定的,就像我最初做的那样.

我在条形图上为我的x轴使用了一个长的毫秒时间戳.我意识到默认情况下MPAndroidChart将条形宽度设置为0.85f.想想这意味着什么.我的第一个时间戳是1473421800000f,下一个是1473508200000f:相差86400000f!现在,当每对观测值之间有86400000f时,我怎么能看到一个0.85f宽的条形？要解决此问题,您需要执行以下操作:

barData.setBarWidth(0.6f * widthBetweenObservations);

因此,上面将条形的宽度设置为等于观察之间距离的60%.