itemCount: (widget.userbio.resimler?.length!=null) ? 0:(widget.userbio.resimler?.length!>9)?9:widget.userbio.resimler?.length,
error:
error: The operator '>' can't be unconditionally invoked because the receiver can be 'null'. (unchecked_use_of_nullable_value at [ui_profile_instagram] lib\pages\profile.dart:220)
hello how to fix this error ?
widget.userbio.resimler?.length!>9
ı need compare
CodePudding user response:
The short answer is to change it to widget.userbio.resimler!.length!
.
The long answer is to introduce a local variable. Something like:
final l = widget.userbio.resimler?.length;
You can then test l
for null and the compiler will know that after you've tested it, it can't be null. (Note this only works for local variables - hence why you should add one.)
if (l != null) {/* in this block l cannot be null*/}
so
final l = widget.userbio.resimler?.length;
itemCount: l == null ? 0 : l > 9 ? 9 : l;
Best of all user a null aware operator:
var l = widget.userbio.resimler?.length ?? 0;
if (l > 9) l = 9;