Android: mpandroidchart not shown properly

Question

I am working on a groupped Barchart using mpandroidchart library:

Code:

public void drawing_length(String length)
    {
        ArrayList<String> xx = new ArrayList<String>();
        ArrayList<String> yy = new ArrayList<String>();
        ArrayList<String> zz = new ArrayList<String>();

        int L = 7;
        if (length.equals("7days"))
        {
            L = 7;
        }
        if (length.equals("14days"))
        {
            L = 14;
        }
        if (length.equals("30days"))
        {
            L = 30;
        }
        if (L > x.size())
        {
            L = x.size();
        }
        for (int g=0; g<L; g++)
        {
            xx.add(x.get(g));       // newest first, oldest last
            yy.add(y.get(g));
            zz.add(z.get(g));
        }

        Collections.reverse(xx);        //oldest first, newest last, i.e. sequential
        Collections.reverse(yy);
        Collections.reverse(zz);
        setupGrouppedChart(xx,yy,zz);
    }

public void setupGrouppedChart(ArrayList<String> x, ArrayList<String> y1, ArrayList<String> y2)
    {
        float barWidth;
        float barSpace;
        float groupSpace;

        barWidth = 0.3f;
        barSpace = 0f;
        groupSpace = 0.4f;

        ll_combined_chart.setVisibility(View.GONE);
        ll_scatteredchart.setVisibility(View.GONE);
        ll_groupped_barchart.setVisibility(View.VISIBLE);

        chart_grouppedBar = (BarChart) findViewById(R.id.chart_grouppedBar);
        chart_grouppedBar.getDescription().setEnabled(false);
        chart_grouppedBar.setBackgroundColor(Color.TRANSPARENT);
        chart_grouppedBar.setDrawGridBackground(false);
        chart_grouppedBar.setPinchZoom(false);      
        chart_grouppedBar.setScaleEnabled(false);
        chart_grouppedBar.setDrawBarShadow(false);
        chart_grouppedBar.setDrawValueAboveBar(false);
        chart_grouppedBar.setHighlightFullBarEnabled(false);
        chart_grouppedBar.setHighlightPerDragEnabled(false);
        chart_grouppedBar.setHighlightPerTapEnabled(false); 
        chart_grouppedBar.setDoubleTapToZoomEnabled(false);
        chart_grouppedBar.getXAxis().setDrawGridLines(false);
        chart_grouppedBar.getAxisLeft().setDrawGridLines(false);
        chart_grouppedBar.getAxisRight().setDrawGridLines(false);
        chart_grouppedBar.getAxisRight().setEnabled(false);
        chart_grouppedBar.animateXY(800, 800);
        chart_grouppedBar.getDescription().setText("This is testing Description");
        chart_grouppedBar.setVisibleXRangeMaximum(14f);

        Utilities.custom_toast(Stat.this, "Xsize=" + x.size(), "gone", "short");
        final String[] x_name = new String[x.size()];
        for (int j = 0;  j <x.size(); j++)
        {
            String[] temp = x.get(j).split("-");
            x_name[j] = temp[0] + "/" + temp[1];
        }
        XAxis xLabels = chart_grouppedBar.getXAxis();
        xLabels.setPosition(XAxis.XAxisPosition.BOTTOM);
        xLabels.setGranularity(1f);

        xLabels.setValueFormatter(new IAxisValueFormatter()
        {
            @Override
            public String getFormattedValue(float value, AxisBase axis)
            {
                return x_name[(int) value % x_name.length];
            }
        });

        BarDataSet set1, set2;
        ArrayList<BarEntry> valueSet1 = new ArrayList<>();
        ArrayList<BarEntry> valueSet2 = new ArrayList<>();
        for (int i = 0; i < x_name.length; i++)
        {
            float val1 = Float.parseFloat(y1.get(i));
            BarEntry v1e1 = new BarEntry(i, val1);
            valueSet1.add(v1e1);

            float val2 = Float.parseFloat(y2.get(i));
            BarEntry v1e2 = new BarEntry(i, val2);
            valueSet2.add(v1e2);
        }

        if (chart_grouppedBar.getData() != null && chart_grouppedBar.getData().getDataSetCount() > 0)
        {
            set1 = (BarDataSet) chart_grouppedBar.getData().getDataSetByIndex(0);
            set2 = (BarDataSet) chart_grouppedBar.getData().getDataSetByIndex(1);

            set1.setValues(valueSet1);
            set2.setValues(valueSet2);

            chart_grouppedBar.getData().setHighlightEnabled(false);
            chart_grouppedBar.groupBars(0, groupSpace, barSpace);
            chart_grouppedBar.getData().notifyDataChanged();
            chart_grouppedBar.notifyDataSetChanged();
        }
        else
        {
            set1 = new BarDataSet(valueSet1, "A");
            set1.setColor(getResources().getColor(R.color.pink_light));
            set2 = new BarDataSet(valueSet2, "B");
            set2.setColor(getResources().getColor(R.color.purple1));

            BarData data = new BarData(set1, set2);
            //data.setValueFormatter(new LargeValueFormatter());
            //data.setValueTypeface(mTfLight);

            data.setValueFormatter(new MyValueFormatter());
            chart_grouppedBar.setData(data);
            chart_grouppedBar.getBarData().setBarWidth(barWidth);
            chart_grouppedBar.getXAxis().setAxisMaximum(0 + chart_grouppedBar.getBarData().getGroupWidth(groupSpace, barSpace) * x_name.length);
            chart_grouppedBar.getAxisLeft().setAxisMinimum(0);
            chart_grouppedBar.getAxisLeft().setValueFormatter(new MyYAxisValueFormatter());
            chart_grouppedBar.getData().setHighlightEnabled(false);
            chart_grouppedBar.groupBars(0, groupSpace, barSpace);
            chart_grouppedBar.invalidate(); // refresh
        }
    }

Screen capture:

Question:

1. The legend for the x-axis is shifted. How can it be adjusted?
2. There should be 9 entries but it is now only showing 7 entries. I suspect it is on the right but the screen cannot be scrolled to the right. The toast report the size is 9 correctly. How could the chart be scrollable?
3. The Y-axis is also wrong. The height of the bars do not match with the Y-axis.

Thank you.

Answer 1

Hard-Coded bar width is the problem.Find bar width dynamically like below

((1.00f- 0.20f) / barEntryCount) - 0.05f

where

0.05f -> Bar Spacing;
0.20f -> Group Spacing;

Please read this thread.

Regarding alignment of X Axis Labels (Question 1)

do like following

if (dataSets.size() > 1) {
   barChart.getXAxis().setCenterAxisLabels(true);
else
   barChart.getXAxis().setCenterAxisLabels(false);

Regarding the 2nd question

Please verify that your dataset count is 9.If you given 9 elements in dataset surly ,it will plot.Please check other view properties including view clipping.

Answer 2

For your 2nd question

How could the chart be scrollable?

chart_grouppedBar.setDragEnabled(true); 

Reference link

For 3rd question

The Y-axis is also wrong. The height of the bars do not match with the Y-axis.

try to set Min & Max value of axis and label count. For example:

    chart_grouppedBar.getAxisLeft().setAxisMaxValue(MAX VALUE FROM YOUR DATASET);
    chart_grouppedBar.getAxisLeft().setLabelCount(8, true);

reference link