1. You can register for MouseLeftButtonDown
of the chart and if the e.ClickCount == 2 show trackball point by switching ChartTrackBallBehavior.ShowIntersectionPoints
from false to true.
2. By using the TrackInfoUpdated
event of the ChartTrackBallBehavior
, you can get the X and Y of the closest data point. Using this information, you can create a new CartesianCustomAnnotation
, set its Vertical/Horizontal Value and add it to the chart annotations collection.
3. After you add an CartesianCustomAnnotation you can register for its MouseLeftButtonDown
. In the Down
handler register for the MouseMove
event and in the Up
event - unregister the MouseMove
event. In the MouseMove handler you get the mouse position relative to the chart and using the Conversion API
calculate the new position of the CartesianCustomAnnotation.
4. [Same as 2.]
I hope this helps.
the Telerik team