Tooltip not rendering when line chart has only one data point per series

[Rebecca Kekelishvili]

I have a Line chart that displays fine and shows tooltip when there is more than 1 data point in the series. However, I experience the following error when I pass in only one data point to a line chart: 

The error brings me to the following line in the code:

tooltipArgs = TooltipArgs(

_chart is SfCartesianChart

? currentSeries._segments[0]._seriesIndex

: currentSeries,

Error below:

════════ Exception caught by rendering library ═════════════════════════════════

The following RangeError was thrown during paint():

RangeError (index): Invalid value: Valid value range is empty: 0

The relevant error-causing widget was

SfCartesianChart-[<'11_chart'>]

lib/…/line_chart_widget/line_chart_widget_view.dart:79

When the exception was thrown, this was the stack

#0      List.[] (dart:core-patch/growable_array.dart:177:60)

#1      _TooltipPainter._renderTooltip

package:syncfusion_flutter_charts/…/user_interaction/tooltip_painter.dart:700

#2      TooltipBehaviorRenderer.onPaint

package:syncfusion_flutter_charts/…/user_interaction/tooltip.dart:883

#3      _TooltipPainter.paint

package:syncfusion_flutter_charts/…/user_interaction/tooltip_painter.dart:673

#4      RenderCustomPaint._paintWithPainter

package:flutter/…/rendering/custom_paint.dart:531

...

The following RenderObject was being processed when the exception was fired: RenderCustomPaint#b5208 relayoutBoundary=up4

RenderObject: RenderCustomPaint#b5208 relayoutBoundary=up4

    parentData: <none> (can use size)

    constraints: BoxConstraints(0.0<=w<=378.0, 0.0<=h<=300.0)

    size: Size(0.0, 0.0)

I would appreciate any pointers,

Thank you

[Sriram Kiran Senthilkumar]

Hi Rebecca, 

  

Greetings from Syncfusion. The reported issue has been resolved already and will be available in upcoming weekly patch release which is expected to be rolled out on February 2, 2021. We will keep you posted once the weekly patch release has been rolled out and we appreciate your patience until then. 

  

Thanks, 

Sriram Kiran 

[Dharanitharan Palanisamy]

Hi Rebecca,

We are happy to inform you that the reported issue has been fixed in our latest version v18.4.41. Now the tooltip for a single data point will render and does not throw any exception. Please upgrade our chart package to the latest version from the following link.

Latest version: https://pub.dev/packages/syncfusion_flutter_charts/versions/18.4.41

Thanks,
Dharanitharan. P