[英]Get data from firebase Realtime database
I want to get data from firebase in sorted manner, I tried below method but its not working propely and collects all the data.我想以排序方式从 firebase 获取数据,我尝试了以下方法,但它无法正常工作并收集所有数据。
Here is the image for my firebase database:这是我的 firebase 数据库的图像:
DatabaseReference databaseRef = FirebaseDatabase.getInstance().getReference();
String input = "G";
Date cd = Calendar.getInstance().getTime();
SimpleDateFormat df = new SimpleDateFormat("dd-MMM-yyyy", Locale.getDefault());
String formattedDate = df.format(cd);
FirebaseUser currentUser = mAuth.getCurrentUser();
DatabaseReference data = databaseRef.child("Data").child(currentUser.getUid()).child(formattedDate.toString()).child(medname.toString());
databaseRef.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapshot) {
List<String> data = new ArrayList<String>();
for (DataSnapshot postSnapshot : snapshot.getChildren()) {
data.add(postSnapshot.getValue().toString());
}
Log.d("datafriebase",""+data);
}
I want to get data in sorted manner, like value of 1, value of 2 but i am getting whole database我想以排序方式获取数据,例如值 1,值 2,但我正在获取整个数据库
You're getting the whole database, because you're reading from databaseRef
, which you initialized as:您正在获取整个数据库,因为您正在从databaseRef
读取数据,您将其初始化为:
DatabaseReference databaseRef = FirebaseDatabase.getInstance().getReference();
To get only the nested data, read from data
, which you set to reference that path:要仅获取嵌套data
,请从设置为引用该路径的 data 中读取:
DatabaseReference data = databaseRef.child("Data").child(currentUser.getUid()).child(formattedDate.toString()).child(medname.toString());
So:所以:
data.addValueEventListener(new ValueEventListener() {
...
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