isValid property

1. flutter_widget_gql package
2. documentation
3. graphql/gamification-challenge.graphql
4. Query$getUpcomingChallengesByTargetAndUserAudiencePaginated$getUpcomingChallengesByTargetAndUserAudiencePaginated$objects$winners$user$phone
5. isValid property

Query$getUpcomingChallengesByTargetAndUserAudiencePaginated$getUpcomingChallengesByTargetAndUserAudiencePaginated$objects$winners$user$phone class