Smart Event

package com.example.smart_event_monitor;

import android.app.DownloadManager;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;
import android.widget.TextView;

import com.firebase.ui.database.FirebaseRecyclerAdapter;
import com.google.firebase.database.ChildEventListener;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.Query;
import com.google.firebase.database.ValueEventListener;
import com.squareup.picasso.Picasso;

import java.util.UUID;

public class MainActivity extends AppCompatActivity {

    private static final String UUID_KEY = "_UUID";
    private static final String PREFS_NAME = "MyPrefs";

    private RecyclerView recyclerView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Post to initial data to Firebase when device power on
        initMonitor();

        // Set path to node on Firebase
        DatabaseReference myRef = FirebaseDatabase.getInstance().getReference().child("monitors").child(getDeviceId());

        // Set view for display data from Firebase
        FirebaseRecyclerAdapter<Monitor, MonitorViewHolder> adapter = new FirebaseRecyclerAdapter<Monitor, MonitorViewHolder>(
                Monitor.class,
                R.layout.individual,
                MonitorViewHolder.class,
                myRef
        ) {
            @Override
            protected void populateViewHolder (MonitorViewHolder viewHolder, Monitor model, int position) {
                viewHolder.setDescription(model.getDescription());
                viewHolder.setImage(model.getImage());
                viewHolder.setTitle(model.getTitle());
            }
        };

        recyclerView = (RecyclerView) findViewById(R.id.recyclerview);
        recyclerView.setHasFixedSize(true);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        recyclerView.setAdapter(adapter);
    }

    private void initMonitor() {
        DatabaseReference mRootRef = FirebaseDatabase.getInstance().getReference();
        DatabaseReference mMonitorRef = mRootRef.child("monitors");
        mMonitorRef.child(getDeviceId()).child(getDeviceId()).child("title").setValue("TEST");
        mMonitorRef.child(getDeviceId()).child(getDeviceId()).child("description").setValue("TEST");
        mMonitorRef.child(getDeviceId()).child(getDeviceId()).child("image").setValue("https://firebasestorage.googleapis.com/v0/b/testfirebase1-410d9.appspot.com/o/templates%2Fwreath_1.jpg?alt=media&token=efcd6e75-d1fb-4248-b793-a7729876619d");
    }

    private String getDeviceId() {
        SharedPreferences prefs = getSharedPreferences(PREFS_NAME, 0);
        // Generate UUID
        if(!prefs.contains(UUID_KEY)) {
            prefs.edit().putString(UUID_KEY, UUID.randomUUID().toString()).apply();
        }
        return prefs.getString(UUID_KEY, UUID.randomUUID().toString());
    }

    public static class MonitorViewHolder extends RecyclerView.ViewHolder {
        TextView text_description;
        ImageView imageview;
        TextView text_title;
        // Display Image & Text on monitor
        public MonitorViewHolder(View itemView) {
            super(itemView);
            text_description = (TextView) itemView.findViewById(R.id.description);
            imageview = (ImageView) itemView.findViewById(R.id.imageview);
            text_title = (TextView) itemView.findViewById(R.id.title);
        }

        public void setTitle(String title) {
            text_title.setText(title);
        }

        public void setDescription(String description) {
            text_description.setText(description);
        }

        public void setImage(String image) {
            Picasso.with(imageview.getContext()).load(image).into(imageview);
        }
    }
}