Android Firebase - Can't receive proper JSON from Firebase snapshot

Question

My android app connects to Firebase and pulls "Alert Objects" that are sent there by my server.

When I export the data from Firebase, I get a beautifully formated JSON representation of the data.

Problem: When I pull the data to my android device using a DataSnapshot, the data has '=' (equals signs) instead of ':' (semicolons). Also the quotations are not there.

When I try to do something like JSONObject alert = new JSONObject(data.getValue().toString()); I get errors for obvious reasons. I say obvious because if you look at what my code prints to the console you can see that it is no longer in valid JSON format.

A friend mentioned that I need to do something with encoding but we didn't have time to discuss it.

How can I iterate through these (kinda weird) Alert Objects that I have created and turn them into JSON objects within my Java so that I can access their properties like alert.date and alert.message.

I thought screenshots would help you see what I am doing. The firebase is not secured at all so you can feel free to take a look at it. It won't really do much and when I go to production I will be moving it anyways.

I am sure this is a super easy question to answer, I am just not too well versed with JSON and encoding as a whole.

Thanks!

Answer 1

you can it using gson library

       public void onChildAdded(DataSnapshot dataSnapshot, String s) {

            /*JSONObject jsonObject = null;
            try {
                jsonObject=new JSONObject();

            } catch (JSONException e) {
                e.printStackTrace();
            }*/
            Gson gson = new Gson();
            String s1 = gson.toJson(dataSnapshot.getValue());
            JSONArray object = null;
            try {
                object = new JSONArray(s1);
            } catch (JSONException e) {
                e.printStackTrace();
            }

            JSONArray jsonArray = object;

            Log.e("string", s1);

        }

Answer 2

You cannot access JSON natively in Java.

But the Firebase DataSnapshot class provides everything you need.

If you have a DataSnapshot of the data at the fbAlerts in your screenshot, you can print the date+message and recipients for each:

for (DataSnapshot alert: alerts.getChildren()) {
  System.out.println(alert.child("date").getValue();
  System.out.println(alert.child("message").getValue();
  for (DataSnapshot recipient: alert.child("recipients").getChildren()) {
    System.out.println(recipient.child("name").getValue();
  }
}

Alternatively, you can build a Java class that represents an alert. See the Firebase guide on reading data in Android for examples of that.