c++qtchartsqmlqchartview

February is missing from Qt charts (QML) datetime axis

I have created a QML chart

ChartView {
    id: chart
    anchors.fill: parent
    antialiasing: true
    ValueAxis {
        id: axisY
        tickCount: 3
    }
    DateTimeAxis {
        id: xTime
    }
    SplineSeries {
        id: chartseries
        pointsVisible: true

        pointLabelsVisible: false
        useOpenGL: true
        axisX: xTime
        axisY: axisY
    }
}

I am also appending at the beginning of each month to the chart. Tooltip on tick points are correct. On X axis Qt itself is doing the same as it like . How to adjust it manually

 Xaxis->setTickCount(commonmap.size());
QMap<qint64,double>::const_iterator i = commonmap.constBegin();
while (i != commonmap.constEnd())
{
  splineseries->append(i.key(),i.value());
  ++i;
}

enter image description here

Solution

  • I have found an answer to this problem (may not be the right way...But can be solved) Step to achieve the solution -

    1. Find Last date of the last month (say June 30)
    2. setMax date of QDateTimeAxis.

    It works Because Qt divides the days between Start date and end date equally and distribute across X axis based ob the tick count .

    With the values above in the question will get a chart as shown in the Image

    enter image description here

    [

    Xaxis->setMin(QDateTime::fromMSecsSinceEpoch(commonmap.firstKey()));
Xaxis->setMax(getLastDate());

getLastDate()
{
   QDate firstdate = 
   QDateTime::fromMSecsSinceEpoch(commonmap.lastKey()).date();
   int month =  firstdate.month();
   int day = firstdate.day();
   int addday = 0;
   switch (month) {
    case 1:
    case 3:
    case 5:
    case 7:
    case 8:
    case 10:
    case 12:
       addday = 31- day;
      break;
    case 4:
    case 6:
    case 9:
    case 11:
       addday = 30- day;
     break;
    case 2:
        if(firstdate.isLeapYear(firstdate.year()))
        {
            addday = 29- day;
        }
        else
       {
          addday = 28- day;
       }
       break;

   }

return (QDateTime::fromMSecsSinceEpoch(commonmap.lastKey()).addDays(addday));
 }