为什么我在反应原生 Firebase 成功异步调用后收到错误

Question

I'm still learning about react-native.

After I make a successful call to delete a file from my record, I then try to attempt to print out a success message to the console but instead I'm receiving an error stated below. Any pointers to where I'm going wrong?

TypeError: undefined is not an object (evaluating 
'server.deleteLocation(userUID, {
    streetName: streetName,
    long: long,
    lat: lat
  }).then')

Here is my firebase call (in a seperate file. Ive checked this code and it 100% works:):

const deleteLocation = (uid, locationObject) => {
 console.log('firebase deleteLocation............ START');

 firestore()
 .collection('Users')
 .doc(uid)
 .update({
  locations: firestore.FieldValue.arrayRemove({
     streetName: locationObject.streetName,
     longitude: locationObject.long,
     latitude: locationObject.lat,
   }),
 })
 .then(() => {
   console.log('firebase deleteLocation............ SUCCESS');
 })
 .catch((errorsss) => {
   console.log('firebase deleteLocation............ FAILED');
   throw errorsss;
  });
 };

Here is my calling code (here is where the problem occurs)

             ........imports
 import * as server from '../api/firebase';


deleteLocation = (streetName, long, lat) => {
server
  .deleteLocation(userUID, { streetName, long, lat })
  .then(() => {
    console.log('DELETE WAS SUCESSSS');
  })
  .catch((error) => {
    console.log('ERROR CAUGHT IN DELETING PROGRAM');
    console.log(error);
  });
 };

Answer 1

Your method deleteLocation that you have written on separate file is not async method, and you are trying to access .then on that method so that's why this error is coming. Here is the solution.

Make your deleteLocation async:

const deleteLocation = async (uid, locationObject) => {
  console.log('firebase deleteLocation............ START');

  await firestore()
  .collection('Users')
  .doc(uid)
  .update({
    locations: firestore.FieldValue.arrayRemove({
      streetName: locationObject.streetName,
      longitude: locationObject.long,
      latitude: locationObject.lat,
    }),
  })
  .catch((errorsss) => {
    console.log('firebase deleteLocation............ FAILED');
    throw errorsss;
  });
};

Now, you can access .then and error will gone.