Improve custom trackball tooltip positioning + avoid hiding it completely

[WieFel]

I am currently trying to solve #495 myself. Open for any help @Yuvaraj-Gajaraj.

Idea:

• Show custom trackball tooltip (when builder: is set) on the right side of trackball line, as long as trackball line is in left half of chart area
• Show custom trackball tooltip on the left side of trackball line, as long as trackball line is in right half of chart area
• Resize the tooltip based on the available width

What has been done:

• show grouped (groupAllPoints: true) custom trackball tooltip always either on left or on right side of trackball line and constrain its width based on available width
• adapt trackball tooltip for non-grouped case

Closes #495.

[WieFel]

hi, any news about merging this?

[ghost]

Hi @WieFel ,

We have positioned the trackball tooltip inside the plot area and changes are moved to Charts version 27.1.48 version. Please upgrade the Charts to latest version:
https://pub.dev/packages/syncfusion_flutter_charts/versions/27.2.2

Regards,
Lavanya A.