@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    barChart = (BarChart) findViewById(R.id.bargraph);

    conexionBD();


    ArrayList<BarEntry> barEntries = new ArrayList<>();

    for (a = 1; a == i; a++) {

        barEntries.add(new BarEntry(Float.parseFloat(ra), i));

    }


    BarDataSet barDataSet = new BarDataSet(barEntries, "  EDADES");

    ArrayList<String> Day = new ArrayList<>();
    for (i = 0; i > 0; i++) {
        Day.add(rs);
    }


    BarData theData = new BarData(Day, barDataSet);
    barChart.setData(theData);

    barChart.setVisibleXRange(20); // allow 20 values to be displayed at once on the x-axis, not more
    barChart.moveViewToX(10);

    barChart.setTouchEnabled(true);
    barChart.setDragEnabled(true);
    barChart.setScaleEnabled(true);

    barChart.setDescription("INDICADOR DE EDADES OPDM");
}
public Connection conexionBD() {
    Connection conexionBD = null;
    try {
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);
        Class.forName("net.sourceforge.jtds.jdbc.Driver").newInstance();
        conexionBD = DriverManager.getConnection("jdbc:jtds:sqlserver://192.168.1.67;databaseName=opdm;user=Jose;password=123;");

        Statement sentencia = conexionBD.createStatement();
        ResultSet rs = sentencia.executeQuery("select nombre from usuarios");
        Statement sentenia1 = conexionBD.createStatement();
        ResultSet ra = sentenia1.executeQuery("select codigo from ususarios");


        while (rs.next()&& ra.next()) {


        }
    } catch (Exception e) {
        Toast.makeText(getApplicationContext(), e.getMessage(), Toast.LENGTH_SHORT).show();
    }
    return conexionBD;
}