why my switchCase have error The body might complete normally, causing 'null' to be returned, but the return type, 'String', is a potentially non-nullable type. Try adding either a return or a throw statement at the end.dartbody_might_complete_normally
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why my switchCase have error The body might complete normally, causing 'null' to be returned, but the return type, 'String', is a potentially non-nullable type.
Try adding either a return or a throw statement at the end.dartbody_might_complete_normally