AChartGraph with multiple lines

Question

I want to get some values from a table and store them in a multiple line chart. When I use only one column (fat) it displays a graph correctly, but when i add another column or two it gives me an error saying : Dataset and renderer should not be null and should not have the same number of series. Could you please help me fix the error?

  public XYMultipleSeriesDataset getFatDataset() {

    XYMultipleSeriesDataset dataset = new XYMultipleSeriesDataset();
    Cursor c = database.rawQuery("select * from dailystats;", null);
    float i = 1.0f;

    c.moveToFirst();
    XYSeries seriesFat = new XYSeries("Fat");
    while(!c.isAfterLast()) {
        seriesFat.add(i++, c.getDouble(2));

        c.moveToNext();
    }
    dataset.addSeries(seriesFat);

   i = 1.0f;
    c.moveToFirst();
    XYSeries seriesProtein = new XYSeries("Protein");
    while(!c.isAfterLast()) {

        seriesProtein.add(i++, c.getDouble(3));

        c.moveToNext();
    }
    dataset.addSeries(seriesProtein);

    c.moveToFirst();
    i = 1.0f;
    XYSeries seriesCarbs = new XYSeries("Carbs");
    while(!c.isAfterLast()) {

        seriesCarbs.add(i++, c.getDouble(4));
        c.moveToNext();
    }
    dataset.addSeries(seriesCarbs);

    return dataset;
}

And here is the code for generating the graph:

public class ChartActivity {

public Intent getIntent(Context context)

{

XYMultipleSeriesDataset dataset = new XYMultipleSeriesDataset();


XYMultipleSeriesRenderer mrenderer = new XYMultipleSeriesRenderer();
XYSeriesRenderer renderer = new XYSeriesRenderer();
mrenderer.addSeriesRenderer(renderer);

DatabaseAdapter dba = new DatabaseAdapter(context);
dba.open();


Intent intent = ChartFactory.getLineChartIntent(context, dba.getFatDataset(), mrenderer,"line graph");
dba.close();

return intent;

}

score 0 · Accepted Answer · answered May 04 '12 at 11:00

The error reported is quite clear: Dataset and renderer should not be null and should not have the same number of series means that you're using a different number of series and series renderer. Infact, you're adding two datasets:

//...
dataset.addSeries(seriesFat);
//....
dataset.addSeries(seriesCarbs);
//....

But you only have one XYSeriesRenderer():

mrenderer.addSeriesRenderer(renderer);

In my opinion your code should start working simply adding another renderer to the XYMultipleSeriesRenderer(), please try with these two lines:

XYSeriesRenderer renderer2 = new XYSeriesRenderer();
mrenderer.addSeriesRenderer(renderer2);

AChartGraph with multiple lines

1 Answers1