Does anyone have idea how to solve this error : "only safe (?.) Or non-null asserted(!!.) Calls are ...

# android

[Jinal Barot]

Does anyone have idea how to solve this error : "only safe (?.) Or non-null asserted(!!.) Calls are allowed on a nullable receiver of type cursor?"

I'm trying to extract contacts using ContactsContract content provider by query which return response as a Cursor

[gildor]

Cursor can be null, you can see it in query method signature, it annotated with @Nullable

Just check for cursor nullability in your condition and Kotlin smart cast will handle it for you:

if (cursor != null && cursor.count > 0)

[gildor]

Also, a side note, no need to use var, you can see that IDE suggest you to use val, it will also help with smart cast in some cases

[gildor]

Are you familiar with Kotlin nullale types? If not, I would recommend first check documentation:
https://kotlinlang.org/docs/reference/null-safety.html

Also, #getting-started is good channel if you just started and have questions about basic language features

[Lou Morda]

i was a kotlin newbie not too long ago, double bang (!!) is always best to avoid, from what i've read. i got dinged pretty hard on an interview problem for using double bang (rightfully so i believe)