用于图表引擎的 Android 数组

Question

我正在尝试使用库 aChartengine 在条形图中显示查询结果。要查看在将它们放入 ArrayList 之前获取的所有数据，然后在 for 循环中输入 double 组时？这是我目前所拥有的。

private void grafico(String years){
   SQLiteDatabase db = new ReHelper(getActivity()).getReadableDatabase();
   ArrayList <Double> dettagli = new ArrayList<Double>();
   String sql ="SELECT number FROM Table GROUP BY motion";

   Cursor c = db.rawQuery(sql, null);
   while (c.moveToNext()){
      double number= c.getDouble(0);
      dettagli.add(number);

      XYSeries eeSeries = new XYSeries("series");
      for(int i=0;i<...;i++){           
         eeSeries.add(i);
      }
  }
}

Answer 1

如果我理解你的问题，你应该这样做:

获取您的数据:

XYSeries eeSeries = new XYSeries("series");

int i = 0;
Cursor c = db.rawQuery(sql, null);
while (c.moveToNext()){
  double number= c.getDouble(0);
  eeSeries.add(i++, number);
}
c.close(); 

准备您的图表/渲染器:

// Create a dataset to hold each series
XYMultipleSeriesDataset dataset = new XYMultipleSeriesDataset();
// Add the series to the dataset
dataset.addSeries(eeseries);

// Creating XYSeriesRenderer
XYSeriesRenderer renderer = new XYSeriesRenderer();
renderer.setFillPoints(true);
renderer.setLineWidth(2);
renderer.setDisplayChartValues(true);

// Creating a XYMultipleSeriesRenderer to customize the whole chart
XYMultipleSeriesRenderer multiRenderer = new XYMultipleSeriesRenderer();
multiRenderer.setXLabels(0);
multiRenderer.setChartTitle("Title");

multiRenderer.addSeriesRenderer(renderer);

显示图形的最简单方法是使用 ChartFactory:

Intent intent = ChartFactory.getBarChartIntent(
    getBaseContext(), dataset, multiRenderer, Type.DEFAULT);
startActivity(intent);