javascript - How after navigate.goBack, listen to firebase? React Native -


i have 2 screens: , b

in a, listen firebase on() start listen in componentdidmount(). , if there live database update working. before change screen in componentwillunmount() detach firebase ref listener. working until now.

but after change screen b , going navigate.goback screen a, don't updates because, don't start listen again after, componentwillunmount()!

the problem navigate.goback don't fire componentdidmount screen a!

what should do?


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