Why is the VSCode report an error "Evaluation of this constant expression throws an exception."

[cn1001wang]

I'm a beginner of flutter. download from git . after run "flutter pub get" ,the VsCode report an error “Evaluation of this constant expression throws an exception.“

[ashutosh-mulik]

It's because you defined kPrimaryGradient as constant. Generally, in order to have a widget that is compile-time constant, all of its properties should also be compile-time constants.