who can help me with this error that I have been trying to solve for almost 2 days and I have not been able to.
I have done several things, removed flutter and reinstalled it, flutter clean and flutter pub get and tried to update all the dependencies but nothing has worked, what do you think it could be? Thank you very much in advance.
CodePudding user response：
Add null aware operator(?.) before instance like this,
Replace,
SchedulerBinding.instance!.addPostFrameCallBack
To,
SchedulerBinding?.instance!.addPostFrameCallBack
CodePudding user response：
Use latest version of sliding_up_panel and go to this location and delete the older versions of sliding_up_panel
OR
you can just directly delete sliding_up_panel from given location if you are not using the package in current project
C:\flutter\.pub-cache\hosted\pub.dartlang.org\