如果您要查询 100 公里半径内的用户，您如何将自己（当前用户）排除在查询之外？
因为当 onDocumentMoved 触发时，如果您是唯一一个在输入文档时触发的移动，您将再次获得用户，但您与用户之间的距离不同，因此如果您在 onDocumentEntered 方法中将它们添加到数据库中，您将获得重复的结果. 我解决它的方法是在再次打开应用程序时从数据库中删除所有 usersInRange。我知道这不是完美的解决方案，我正在寻找更好的解决方案。
这是我的代码：
public void getLocation(Location location){
ArrayList<String> docMoved = new ArrayList<>();
listenerRegistration = documentReference.addSnapshotListener(new EventListener<DocumentSnapshot>() {
@Override
public void onEvent(@Nullable DocumentSnapshot value, @Nullable FirebaseFirestoreException error) {
if(value != null && value.exists()){
if (value.get("LocationRange") != null && value.get("AgeRangeFrom") != null && value.get("AgeRangeTo") != null && value.getString("InterestInGender") != null) {
locationRange = (double) value.get("LocationRange");
ageRangeFrom = (double) value.get("AgeRangeFrom");
ageRangeTo = (double) value.get("AgeRangeTo");
interestInGender = value.getString("InterestInGender");
ArrayList<HashMap<Object, Object>> usersInRange = (ArrayList<HashMap<Object, Object>>) value.get("UsersInRange");
geoQuery = geoFirestore.queryAtLocation(new GeoPoint(location.getLatitude(), location.getLongitude()), locationRange);
geoQuery.addGeoQueryDataEventListener(new GeoQueryDataEventListener() {
@Override
public void onDocumentEntered(@NotNull DocumentSnapshot documentSnapshot5, @NotNull GeoPoint geoPoint) {
if (documentSnapshot5.get("age") != null && documentSnapshot5.getString("Gender") != null && documentSnapshot5.get("Images") != null && !documentSnapshot5.getId().equals(user.getUid())) {
age = (long) documentSnapshot5.get("age");
userGender = documentSnapshot5.getString("Gender");
userPhotos = (ArrayList<String>) documentSnapshot5.get("Images");
Location locationNew = new Location(documentSnapshot5.getId());
locationNew.setLatitude(geoPoint.getLatitude());
locationNew.setLongitude(geoPoint.getLongitude());
distanceM = location.distanceTo(locationNew);
distanceKM = (int) Math.round(distanceM / 1000);
if (age >= ageRangeFrom && age <= ageRangeTo && interestInGender.equals("Women") && userGender.equals("Woman")) {
db.collection("UsersFilter").document(user.getUid()).update("UsersInRange", FieldValue.arrayUnion(new User(documentSnapshot5.getString("Name"), age, userPhotos.get(0), documentSnapshot5.getId(), distanceKM, null)));
} else if (age >= ageRangeFrom && age <= ageRangeTo && interestInGender.equals("Men") && userGender.equals("Man")) {
db.collection("UsersFilter").document(user.getUid()).update("UsersInRange", FieldValue.arrayUnion(new User(documentSnapshot5.getString("Name"), age, userPhotos.get(0), documentSnapshot5.getId(), distanceKM, null)));
} else if (age >= ageRangeFrom && age <= ageRangeTo && interestInGender.equals("Everyone")) {
db.collection("UsersFilter").document(user.getUid()).update("UsersInRange", FieldValue.arrayUnion(new User(documentSnapshot5.getString("Name"), age, userPhotos.get(0), documentSnapshot5.getId(), distanceKM, null)));
} else {
db.collection("UsersFilter").document(user.getUid()).update("UsersInRange", FieldValue.arrayRemove(new User(documentSnapshot5.getString("Name"), age, userPhotos.get(0), documentSnapshot5.getId(), distanceKM, null)));
}
}
}
@Override
public void onDocumentExited(@NotNull DocumentSnapshot documentSnapshot1) {
db.collection("UsersFilter").document(user.getUid()).get().addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
@Override
public void onSuccess(DocumentSnapshot documentSnapshot) {
ArrayList<HashMap<Object, Object>> usersInRange = (ArrayList<HashMap<Object, Object>>) documentSnapshot.get("UsersInRange");
if (usersInRange != null && !usersInRange.isEmpty()) {
for (int i = 0; i < usersInRange.size(); i++) {
if (usersInRange.get(i).containsValue(documentSnapshot1.getId())) {
db.collection("UsersFilter").document(user.getUid()).update("UsersInRange", FieldValue.arrayRemove(usersInRange.get(i)));
}
}
}
}
});
}
@Override
public void onDocumentMoved(@NotNull DocumentSnapshot documentSnapshot6, @NotNull GeoPoint geoPoint) {
docMoved.add(documentSnapshot6.getId());
if(!documentSnapshot6.getId().equals(user.getUid())) {
db.collection("UsersFilter").document(user.getUid()).get().addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
@Override
public void onSuccess(DocumentSnapshot documentSnapshot) {
ArrayList<HashMap<Object, Object>> usersInRange = (ArrayList<HashMap<Object, Object>>) documentSnapshot.get("UsersInRange");
if (usersInRange != null && !usersInRange.isEmpty()) {
for (int i = 0; i < usersInRange.size(); i++) {
if (usersInRange.get(i).containsValue(documentSnapshot6.getId())) {
db.collection("UsersFilter").document(user.getUid()).update("UsersInRange", FieldValue.arrayRemove(usersInRange.get(i)));
}
}
}
}
});
}
}
@Override
public void onDocumentChanged(@NotNull DocumentSnapshot documentSnapshot1, @NotNull GeoPoint geoPoint) {
if(docMoved.size() == 1 && docMoved.get(0).equals(user.getUid())){
db.collection("UsersFilter").document(user.getUid()).update("UsersInRange", FieldValue.delete());
}
db.collection("UsersFilter").document(user.getUid()).get().addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
@Override
public void onSuccess(DocumentSnapshot documentSnapshot) {
ArrayList<HashMap<Object, Object>> usersInRange = (ArrayList<HashMap<Object, Object>>) documentSnapshot.get("UsersInRange");
if (usersInRange != null && !usersInRange.isEmpty()) {
for (int i = 0; i < usersInRange.size(); i++) {
if (usersInRange.get(i).containsValue(documentSnapshot1.getId())) {
db.collection("UsersFilter").document(user.getUid()).update("UsersInRange", FieldValue.arrayRemove(usersInRange.get(i)));
}
}
}
}
});
}
@Override
public void onGeoQueryReady() {
}
@Override
public void onGeoQueryError(@NotNull Exception e) {
}
});
}
}
}
});
这是在 ViewPager2 中显示用户的代码：
listenerRegistration = documentReference.addSnapshotListener(new EventListener<DocumentSnapshot>() {
@Override
public void onEvent(@Nullable DocumentSnapshot value, @Nullable FirebaseFirestoreException error) {
if(value != null && value.exists()) {
usersInRange = (ArrayList<HashMap<Object, Object>>) value.get("UsersInRange");
usersInChat = (ArrayList<HashMap<Object, Object>>) value.get("UsersInChat");
imageUrls.clear();
viewPager2Adapter.notifyDataSetChanged();
if (usersInChat != null && !usersInChat.isEmpty() && usersInRange != null && !usersInRange.isEmpty()) {
for (int i = 0; i < usersInChat.size(); i++) {
for (int k = 0; k < usersInRange.size(); k++) {
if (usersInRange.get(k).containsValue(usersInChat.get(i).get("userID"))) {
usersInRange.remove(usersInRange.get(k));
}
}
}
}
if (usersInRange != null && !usersInRange.isEmpty()) {
for (int i = 0; i < usersInRange.size(); i++) {
String profileImage = (String) usersInRange.get(i).get("profilePic");
String userName = (String) usersInRange.get(i).get("name");
long userAge = (long) usersInRange.get(i).get("age");
String userID = (String) usersInRange.get(i).get("userID");
long km = (long) usersInRange.get(i).get("km");
imageUrls.add(new User(userName, userAge, profileImage, userID, km, null));
viewPager2Adapter.notifyDataSetChanged();
}
}
}
}
});