Dirk says rounded corners look better. This now looks a bit
extreme to me and probably the border size should be increased.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
When the user hovers over features in the chart, they should
be presented with more information. For example in bar charts
on the dives the bar represents and the exact value that the
bar represents, etc.
The InformationBox is a simple QGraphicsWidget, which can be
placed on top of QCharts and can show a number of arbitrary
text lines.
When placing the box on the chart, the code attempts to stay
inside the plot area of the chart.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>