import com.github.mikephil.charting.formatter.FillFormatter; //导入依赖的package包/类
/**
 * Sets a custom FillFormatter to the chart that handles the position of the
 * filled-line for each DataSet. Set this to null to use the default logic.
 *
 * @param formatter
 */
public void setFillFormatter(FillFormatter formatter) {

    if (formatter == null)
        mFillFormatter = new DefaultFillFormatter();
    else
        mFillFormatter = formatter;
}
 

import com.github.mikephil.charting.formatter.FillFormatter; //导入依赖的package包/类
@Override
public FillFormatter getFillFormatter() {
    return mFillFormatter;
}
 

import com.github.mikephil.charting.formatter.FillFormatter; //导入依赖的package包/类
private void setData(int count, float range) {

        ArrayList<String> xVals = new ArrayList<String>();
        for (int i = 0; i < count; i++) {
            xVals.add((1990 +i) + "");
        }

        ArrayList<Entry> vals1 = new ArrayList<Entry>();

        for (int i = 0; i < count; i++) {
            float mult = (range + 1);
            float val = (float) (Math.random() * mult) + 20;// + (float)
                                                           // ((mult *
                                                           // 0.1) / 10);
            vals1.add(new Entry(val, i));
        }
        
        // create a dataset and give it a type
        LineDataSet set1 = new LineDataSet(vals1, "DataSet 1");
        set1.setDrawCubic(true);
        set1.setCubicIntensity(0.2f);
        //set1.setDrawFilled(true);
        set1.setDrawCircles(false); 
        set1.setLineWidth(1.8f);
        set1.setCircleRadius(4f);
        set1.setCircleColor(Color.WHITE);
        set1.setHighLightColor(Color.rgb(244, 117, 117));
        set1.setColor(Color.WHITE);
        set1.setFillColor(Color.WHITE);
        set1.setFillAlpha(100);
        set1.setDrawHorizontalHighlightIndicator(false);
        set1.setFillFormatter(new FillFormatter() {
            @Override
            public float getFillLinePosition(ILineDataSet dataSet, LineDataProvider dataProvider) {
                return -10;
            }
        });
        
        // create a data object with the datasets
        LineData data = new LineData(xVals, set1);
        data.setValueTypeface(tf);
        data.setValueTextSize(9f);
        data.setDrawValues(false);

        // set data
        mChart.setData(data);
    }
 

import com.github.mikephil.charting.formatter.FillFormatter; //导入依赖的package包/类
/**
 * Returns the FillFormatter that is set for this DataSet.
 *
 * @return
 */
FillFormatter getFillFormatter();
 

import com.github.mikephil.charting.formatter.FillFormatter; //导入依赖的package包/类
/**
 * Returns the FillFormatter that is set for this DataSet.
 * @return
 */
public FillFormatter getFillFormatter() {
    return mFillFormatter;
}