Rotate the actual values that are displayed in bar chart on Android using AchartEngine

Question

How can I rotate the values that are displayed on top of the bars shown in bar chart in achartengine. I know we can rotate the Y-axis labels using setYLabelsAngle(float angle) but I want to rotate the actual values shown on top of the bars. i.e values shown when you say setDisplayChartValues(boolean display).

I have searched for this feature on AchartEngine, AndroidPlot and AFreeChart but could not find it. Could you provide me a solution or should I implement this feature on my own using Canvas and custom view.

PS I only need to display BarChart in my app.

Answer 1

You cant do this by using any function of renderer etc, If you have source code of achartengine library, you can edit it and achieve your goal.

To rotate text change the drawChartValuesText() inside Barchart class not in XYChart class. Just put the angle of rotation inside drawText() function at both the places as the following

 protected void drawChartValuesText(Canvas canvas, XYSeries series, SimpleSeriesRenderer renderer,
      Paint paint, List<Float> points, int seriesIndex, int startIndex) {
    int seriesNr = mDataset.getSeriesCount();
    int length = points.size();
    float halfDiffX = getHalfDiffX(points, length, seriesNr);
    for (int i = 0; i < length; i += 2) {
      int index = startIndex + i / 2;
      double value = series.getY(index);
      if (!isNullValue(value)) {
        float x = points.get(i);
        if (mType == Type.DEFAULT) {
          x += seriesIndex * 2 * halfDiffX - (seriesNr - 1.5f) * halfDiffX;
        }
        if (value >= 0) {
          drawText(canvas, getLabel(renderer.getChartValuesFormat(), value), x, points.get(i + 1)
              - renderer.getChartValuesSpacing(), paint, 90);

          //Initially 90 was 0 you can change it according to your requirement

        } else {
          drawText(canvas, getLabel(renderer.getChartValuesFormat(), value), x, points.get(i + 1)
              + renderer.getChartValuesTextSize() + renderer.getChartValuesSpacing() - 3, paint, 90);

        //Initially 90 was 0 you can change it according to your requirement


        }
      }
    }
  }

See the changes made inside the drawText() at both places and see the comments.There is not another way to achieve your goal.If it is make me know.