Chartview Lasso Zoom highlight box not shown

[George C.]

Greetings,

In chart view documentation, Lasso Zoom segment, there is a highlight box drawn when Lasso Zoom area is specified via dragging mouse. But when I tested on my side, there is nothing visual drawn and shown when specifying the Lasso Zoom area, however the Lasso Zoom feature works just fine. Is there Anyway to draw a rectangular box corresponding to the area specified for Lasso Zoom like the picture I attached ? Thanks in advance.

[Nadya | Tech Support Engineer]

Hello, George,

The information that you have ChartTrackballController together with LassoZoomController is quite useful in understanding why you don't see the highlighted box when using the lasso selection. Note, ChartTrackBallController and the LassoZoomController rely on the same mouse states in order to provide their functionality. Combining them in a single project might lead to an unexpected result, e.g. the lasso feature can be overridden by the ChartTrackballController.

In this case, if you want to use both trackball controller and lasso zoom controller you should create a custom LassoZoomController and achieve the desired behavior. I would recommend referring to the following KB article: https://www.telerik.com/support/kb/winforms/details/integrating-panzoom-trackball-and-lassozoom-controllers-in-radchartview. I believe this solution would be helpful for you.

I hope this information helps. If you need further assistance please let me know.

Regards,
Nadya
Progress Telerik

[Nadya | Tech Support Engineer]

Hello, George,

It would be strange if you don't see the highlighted box when using the lasso zoom feature. In order to start using this functionality, you should just add LassoZoomController. Then, when you start selecting some area with the mouse the highlighted box would appear and the chart will automatically zoom to the selected area. Please refer to the attached gif file. I have attached a sample project for your reference. Could you give it a try and see how it works.

I hope this helps. Should you have any other questions do not hesitate to contact me.

Regards,
Nadya
Progress Telerik

[George C.]

Hello Nadya,

I checked out the project you attached (BTW, thanks for the project!).

Making comparisons between my project and yours (along with some testing), I could finally find out what lines of code in my project prevent the highlight box from showing up :

Dim controler As New ChartTrackballController()
AddHandler controler.TextNeeded, AddressOf controler_TextNeeded
RadChartView1.Controllers.Add(controler)

Please add a ChartTrackballController to a RadChartView on your side, and see what happens. Thanks for your time.