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[Flutter, Issue] Error: Property 'isEmpty' cannot be accessed on 'String?' because it is potentially null.Try accessing using ?. instead. 본문

TroubleShooting/Flutter Issue

[Flutter, Issue] Error: Property 'isEmpty' cannot be accessed on 'String?' because it is potentially null.Try accessing using ?. instead.

JMcunst 2022. 1. 7. 20:12
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이슈

로그인 페이지 구현중, TextFormField의 isEmpty 사용 시 다음과 같은 이슈 발생.

해결

1. value뒤에 !를 붙임으로써 해결. !는 form이 non-nullable 타입임을 말해준다.

원인

1. Flutter 2.0 이후로 null-safety 가 적용되었기 때문이다. 이슈의 원인은 2.0 이전의 코드를 그대로 차용하면서 생긴 문제였다. 'flutter null-safety'로 구글링 해보면 자세한 사항을 확인 할 수 있다.

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