AChartEngine顯示值對齊

Question

使用AChartEngine，我希望能夠爲XYSeriesRenderer.setChartValuesTextAlign（）指定一種Align.AUTO，使它根據位置不同對齊（實際上，minX點的.LEFT， .RIGHT爲maxX點，其餘爲.CENTER）。這將使所有值易於閱讀。是否有機會在不修改源代碼的情況下實現這樣的顯示？

Answer 1

好的，OOP去救援。 :-)

public class LineChartAligned extends LineChart { 
    private static final long serialVersionUID = 1L; 

    public LineChartAligned(XYMultipleSeriesDataset dataset, XYMultipleSeriesRenderer renderer) { 
    super(dataset, renderer); 
    } 

    @Override 
    protected void drawChartValuesText(Canvas canvas, XYSeries series, SimpleSeriesRenderer renderer, Paint paint, List<Float> points, int seriesIndex, int startIndex) { 
    if (points.size() > 1) { 
     float previousPointX = points.get(0); 
     float previousPointY = points.get(1); 
     for (int k = 0; k < points.size(); k += 2) { 
     if (k == 2) { 
      if (Math.abs(points.get(2) - points.get(0)) > renderer.getDisplayChartValuesDistance() || Math.abs(points.get(3) - points.get(1)) > renderer.getDisplayChartValuesDistance()) { 
      paint.setTextAlign(Align.LEFT); // <<< 
      drawText(canvas, getLabel(renderer.getChartValuesFormat(), series.getY(startIndex)), points.get(0), points.get(1) - renderer.getChartValuesSpacing(), paint, 0); 
      paint.setTextAlign(renderer.getChartValuesTextAlign()); // <<< 
      drawText(canvas, getLabel(renderer.getChartValuesFormat(), series.getY(startIndex + 1)), points.get(2), points.get(3) - renderer.getChartValuesSpacing(), paint, 0); 
      previousPointX = points.get(2); 
      previousPointY = points.get(3); 
      } 
     } 
     else if (k > 2) { 
      if (Math.abs(points.get(k) - previousPointX) > renderer.getDisplayChartValuesDistance() || Math.abs(points.get(k + 1) - previousPointY) > renderer.getDisplayChartValuesDistance()) { 
      paint.setTextAlign((k >= points.size() - 2) ? Align.RIGHT : renderer.getChartValuesTextAlign()); // <<< 
      drawText(canvas, getLabel(renderer.getChartValuesFormat(), series.getY(startIndex + k/2)), points.get(k), points.get(k + 1) - renderer.getChartValuesSpacing(), paint, 0); 
      previousPointX = points.get(k); 
      previousPointY = points.get(k + 1); 
      } 
     } 
     } 
    } 
    else 
     for (int k = 0; k < points.size(); k += 2) 
     drawText(canvas, getLabel(renderer.getChartValuesFormat(), series.getY(startIndex + k/2)), points.get(k), points.get(k + 1) - renderer.getChartValuesSpacing(), paint, 0); 
    } 

} 

Answer 2

有沒有這種確切的行爲，但你可以使用註釋。你可以把它們放在你想要的任何圖形中：

series.addAnnotation(text, x, y);