HomeController gg = Get.put(HomeController());

For example:

​

String? foo; // Nullable String

​

void main() {

  var len = foo!.length; // Runtime error: Null check operator used on a null value

}

Solutions:

You need to find out where you're using the bang operator in your code. Once you are there, you can use any of the following solutions:

​

Use a local variable

​

var f = foo;

if (f != null) {

  var len = f.length; // Safe 

}

Use ?. and ??

​

var len = foo?.length ?? 0; // Provide a default value if foo was null.

// Example Code

String? nullableValue = null;

​

String nonNullValue = nullableValue ?? 'Default Value';

​

print(nonNullValue);

if(str != null){

    len = str!.length;

}else{

    len = 0; //return value if str is null

}