It looks incomplete, but this is a pretty fundamental requirement for any app that uses photos in any way surely... github.com/flutter/flutter/is…
I don't use Flutter yet but a RN guy. But I think its still in Alpha & lots of stuff is not yet done. It took RN 2-3 years to reach where it is & I think if you are using Flutter now, you are on your own. Still you should post it to their group. I am not sure if anyone here is even trying Flutter other than you so I don't think you will find an answer. Also, the community of Flutter is quite defensive. See github.com/flutter/flutter/is… for that.
Something that I posted before on Reddit will give you an idea
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