TrackBall With Multiple Lines in the Same Plot Not Showing TrackBall for all Data Points

[Paurakh Rajbhandary]

I am currently trying to have trackball showing for single SfCartesianChart that contains 3 LineSeries. When I enable the trackBall, the trackball does not go through all the data-points of all the LineSeries. 

My desired behavior is that when the user touches and drags through the chart area, the trackBall would show data points on all of the LineSeries. Currently, the behavior for version ^18.3.50 seems to randomly skip some data-points.

Is there a way to achieve the desired behavior described above?

Thanks

Attachment: Screen_Shot_20201211_at_1.50.26_PM_fad879a3.zip

[Sriram Kiran Senthilkumar]

Hi Paurakh, 

  

Greetings from Syncfusion. We have analyzed your scenario with the provided information at our end and we would like to share some information regarding the trackball rendering behaviour. Currently, the trackball tooltip will get render only for the data points where the current point index is the same for all the series data points in the chart. This is the default behaviour. 

  

Also, we would like to know whether you want to show the nearest data points values also in the activated trackball tooltip when the point index is different for the series data points in that position or how you expect the trackball tooltip? Since we are not clear on your exact requirement, kindly revert us with more information on your requirement in detail so that it will be helpful in providing the solutions sooner. 

 

We have also attached below the user guide links for TrackballBehavior feature available in the chart for your reference. 

·        https://help.syncfusion.com/flutter/cartesian-charts/trackball-crosshair#trackball 

·        https://help.syncfusion.com/flutter/cartesian-charts/trackball-crosshair#label-display-mode 

  

Regards, 

Sriram Kiran 

[Paurakh Rajbhandary]

Thanks for prompt response. Apologies for not being clear.  Here is more detail on my issue.

Lets say for example we are plotting two line series in the same chart.

Line Series 1: (x,y) ={(1,100), (3,200), (5,300)}

Line Series 2: (x,y) ={(2,100), (4,200), (6,300)}

Notice that in the above two line series the x coordinates are on the different x values. In such instances my desired behavior is such that when we tap and drag finger fron the far left to the far right of the chart, the tracker ball should show the data point with x coordinate of 1, 2, 3, 4, 5, 6 with tracker ball marker for each of the data point in both line series. Currently, the behavior is such that either the trackerball skips some data point randomly ot the trackerball does not go beyond certain data point. 

Can you please provide solution to achieve my desired behavior?

[Sriram Kiran Senthilkumar]

Hi Paurakh, 

  

Thanks for the revert. We have analyzed your scenario with provided information at our end and we found that the trackball is skipping for some data points randomly while dragging with the provided test case. We will consider this as a bug and will include the fix in our weekly patch release which is expected to be rolled out by the end of this month. We will update you once the release is rolled out and we appreciate your patience until then. 

  

Regards, 

Sriram Kiran 

[Dharanitharan Palanisamy]

Hi Paurakh, 

  

The reported issue got resolved and the fix will be included in the upcoming weekly patch release which is expected to be rolled out on January 12, 2021. We appreciate your patience until then. 

 

  

Thanks, 

Dharanitharan.P 

[Dharanitharan Palanisamy]

Hi Paurakh, 

  

Thanks for being patience. We are happy to inform you that your reported issue has been fixed in our latest version v18.4.34. Now, the trackball doesn't skip the points, and to resolve the issue please upgrade to our latest version from the following link. 

  

Latest Version: https://pub.dev/packages/syncfusion_flutter_charts/versions/18.4.34 

  

Kindly revert us if you need any further assistance. 

  

Thanks, 

Dharanitharan. P