Multi-selection in a graphic

[PierreRaybaut]

Issue originally submitted here: https://code.google.com/p/guiqwt/issues/detail?id=63

Reported by gaetan.browaeys, Jan 19, 2015

Hello,

I would like to know if it is possible to realize the selection of multi-points of a curve with a "click and slide" with the mouse. See example of plot attached.
I know it is possible by performing a left mouse click and maintaining the Ctrl button press but as I may have many points to select it would be much quicker if I can select different points of a curve in one go.

Thank you really much for your answer.

Regards,

Gaetan