Android Firebase query data

问题

Im trying to query data from firebase database.Below images show data structure. .Im trying to query messages by data(long value is the time in milli seconds).Below is the code :

database.child("Market").child("data").child("messages").orderByKey().startAt("1473777076600").addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {

            MessageFirebaseHelper data = dataSnapshot.getValue(MessageFirebaseHelper.class);

            Object[] messageKeys = data.getMessages().keySet().toArray();

            for(int i=0;i<messageKeys.length;i++){
                Logger.i(TAG, " messages  keys :  " + messageKeys[i]);
            }

        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    });

Below is the error:

W/ClassMapper(8838): No setter/field for 1473777892283 found on class com.app.MessageFirebaseHelper

As the keys change dynamically, creating getter/setter is not correct. How do i get the data and save it ?

TRY 2:

I tried in different way, Query :

database.child("Market").child("data").orderByChild("time")
.startAt("1473777076600").addListenerForSingleValueEvent(new ValueEventListener() {

This does not return any value.

回答1:

Try like this,,

public void onDataChange(DataSnapshot dataSnapshot) {

     for (DataSnapshot eventSnapshot : dataSnapshot.getChildren()) {

            yourModel mModel = eventSnapshot.getValue(yourModel.class);
            Log.e("DATA" ,""+ mModel);   
     }

}

来源：https://stackoverflow.com/questions/39476997/android-firebase-query-data