Hello Everybody,

I'd like to add some describing text to a given QPointF on a chart. I really spent a lot of time trying all of the mapToX's and mapFromX's to map coordinates.
Here's a short wrap up about what I'm doing:

Qt Code: 
  1. // create Chart
  2. chart = new QChart();
  3. chart->createDefaultAxes();
  4.  
  5. // costumize chart
  6. dateTimeAxis = new QDateTimeAxis;
  7.  
  8. categoryAxis = new QBarCategoryAxis();
  9. categoryAxis->append(categoriesList);
  10.  
  11. chart->addAxis(dateTimeAxis,Qt::AlignBottom);
  12. chart->addAxis(categoryAxis, Qt::AlignLeft);
  13.  
  14. // hide casual axes
  15. chart->axisX()->hide();
  16. chart->axisY()->hide();
  17.  
  18. // use QChartView
  19. myChartView = new QChartView(chart);
  20.  
  21. // promote to QMainWindow
  22. layout->addWidget(myChartView);
  23.  
  24. myWidget = new QWidget();
  25. myWidget->setLayout(layout);
  26. setCentralWidget(myWidget);
  27.  
  28. ///////////////////
  29.  
  30. // generate some life
  31. lowerSeries = new QLineSeries();
  32. upperSeries = new QLineSeries();
  33. area = new QAreaSeries(upperSeries, lowerSeries);
  34.  
  35. area->attachAxis(dateTimeAxis);
  36. area->attachAxis(chart->axisY());
  37.  
  38. p1 = QPointF(QDateTime::currentTime.toMSecsSinceEpoch(), 1);
  39. p3 = QPointF(QDateTime::currentTime.toMSecsSinceEpoch(), 5);
  40. p2 = QPointF(QDateTime::currentTime.addSecs(rand_N_ofSec).toMSecsSinceEpoch(), 1);
  41. p4 = QPointF(QDateTime::currentTime.addSecs(rand_N_ofSec).toMSecsSinceEpoch(), 5);
  42.  
  43. lowerSeries << p1 << p2;
  44. upperSeries << p3 << p4;
  45.  
  46.  
  47. // now the problem:
  48. tag = new QGraphicsSimpleTextItem(chart);
  49. tag->setText("any text to describe the point");
  50.  
  51. // how toset the location of the tag properly (near the point)?
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i.e. the point is at (30,60) I'd like to set the tag on (31,61)
a typical QPointF on the chart would look like

Qt Code: 
  1. p1 = QPointF(QDateTime::currentTime.toMSecsSinceEpoch(), 3);
  2. qDebug() << "p:"  << p;
  3.  
  4. p: QPointF(1.51138e+12, 3) // strange numbers due to toMSecSinceEpoche()
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Thanks in advance, Lars