[Performance] Too many repaints while scrolling

[aytunch]

When using a normal ListView.builder or any kind of scrollable, the whole app does not rebuild.
But when using GroupedListView and when we are scrolling the whole page rebuilds causing unnecessary CPU and battery load.

You can see this by enabling;

Future<void> main() async {
  debugRepaintRainbowEnabled = true;
  debugRepaintTextRainbowEnabled = true;

When colors change, rebuild happens for those widgets.

Screen.Recording.2022-07-11.at.23.16.38.mov

[Shamsudeen12]

I have another issue where it takes a while for the screen to open up
Do you think it's related?