(MPAndroidChart) Some labels are not showing in Barchart

Question

I'm using MPAndroidChart(https://github.com/PhilJay/MPAndroidChart).

I made one barchart, but xAxis-2nd value is not showing.

x,y : 1 week, 3회

x,y : 2 week, 0회

x,y : 3 week, 0회

x,y : 4 week, 0회

x,y : 5 week, 0회

Those are my entry values. But like this, 2nd label is not showing in my phone.

I attached source and result screenshot.

ArrayList<BarEntry> entries = new ArrayList<>();
        ArrayList<String> labels = new ArrayList<String>();
        String[] labels2 = new String[ExRegList.length()];
        try {
            exerciseWholeCnt = ExRegList.length();
            for (int i = 0; i < ExRegList.length(); i++) {
                JSONObject obj = ExRegList.getJSONObject(i);
                String week = obj.getString("WEEK");
                int exCnt = obj.getInt("RESULT_COUNT");
                labels.add(week + "주");
                labels2[i] = week+"주";
                entries.add(new BarEntry(i,exCnt));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

        XAxis xAxis = barChart.getXAxis();
        xAxis.setValueFormatter(new IndexAxisValueFormatter(labels2));
        XAxis bottomAxis = barChart.getXAxis();
        bottomAxis.setPosition(XAxis.XAxisPosition.BOTTOM);
        bottomAxis.setDrawLabels(true);
        bottomAxis.setDrawGridLines(false);
        bottomAxis.setDrawAxisLine(true);



        YAxis left = barChart.getAxisLeft();
        left.setAxisMinimum(0);
        left.setAxisMaximum(7);

        BarDataSet barDataSet = new BarDataSet(entries, "01");
        BarData barData = new BarData(barDataSet);

        YAxis rightYAxis = barChart.getAxisRight();
        rightYAxis.setEnabled(false);

        barChart.setData(barData);
        barChart.setDescription(null);
        barChart.setPinchZoom(false);
        barChart.setScaleEnabled(false);
        barChart.setDrawBarShadow(false);
        barChart.setDrawGridBackground(false);
        barChart.animateY(2000);
        barChart.getLegend().setEnabled(false);
        barChart.getData().setValueTextSize(10);

        barChart.getBarData().setValueFormatter(new IValueFormatter() {
            @Override
            public String getFormattedValue(float value, Entry entry, int dataSetIndex, ViewPortHandler viewPortHandler) {
                if (value != 0) {
                    DecimalFormat format = new DecimalFormat("#");
                    return format.format(value) + "회";
                }
                return "";
            }
        });

//            barChart.getXAxis().setValueFormatter(new MyValueFormatter());

        barChart.invalidate();
    }

and the result is.

could anyone help me. Thanks.

Answer 1

Finally, found the problem after looking through source code of the library. You should call setLabelCount. After this line:

  XAxis bottomAxis = barChart.getXAxis();

set count to labels of X axis:

   bottomAxis.setLabelCount(entries.size());

And it will work.

Explaination: Basically, default label count is 6 (if you will not specify) and it doesn't count correctly appropriate labels. In your case you have 5 items, and formatter gets values 0 , 0.8, 1.6, 2.4, 3.2 and 4.0 - 6 values. And this method of the library gives "" value for second value:

   public String getFormattedValue(float value, AxisBase axis) {
        int index = Math.round(value);

        if (index < 0 || index >= mValueCount || index != (int)value)
            return "";

        return mValues[index];
    }

This is library's source code, that gives you label. And in your case it gives "" when rendering 2nd value.

Answer 2

From your code I can guess that there is runtime error in the code/data

 try {
            exerciseWholeCnt = ExRegList.length();
          for (int i = 0; i < ExRegList.length(); i++) {
            JSONObject obj = ExRegList.getJSONObject(i);
            String week = obj.getString("WEEK");
            int exCnt = obj.getInt("RESULT_COUNT");
            labels.add(week + "주");
            labels2[i] = week+"주";
            entries.add(new BarEntry(i,exCnt));
         }

Can you check that loop runs perfectly at the second time and nothing in the log

    } catch (Exception e) {
        **e.printStackTrace();**
    }