[英]On Android, how to get the child identifier that was generated automatically in Firebase Database?
The following image shows what I mean:下图显示了我的意思:
How to get the child identifier that was automatically generated in the Firebase Database (which they are shown in the red rectangles), and bring it to Android Studio?如何获取在 Firebase 数据库中自动生成的子标识符(它们显示在红色矩形中),并将其带到 Android Studio?
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
reference = FirebaseDatabase.getInstance().getReference().child("Usuarios").child(**What must be written here?**); }
You always have to use multiple DatabaseReference objects to approach each nested childs.in your case, it will be something like this to start with.您总是必须使用多个 DatabaseReference 对象来处理每个嵌套的子对象。在您的情况下,开始时会像这样。
DatabaseReference reference=FirebaseDatabase.getInstance().getReference("Usuarios");
reference.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
for(DataSnapshot dataSnapshot: snapshot.getChildren()) {
Log.d("TAG", dataSnapshot.getkey());
reference2 =FirebaseDatabase.getInstance().getReference(dataSnapshot.getkey());
///and so on//
}
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
}
});
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.