Frank van Puffelen puf

## WaitForInitialValue.java
public class Main {
    static ValueEventListener mListener;

    public static void main(String[] args) throws Exception {
        Firebase ref = new Firebase("https://<your-app>.firebaseio.com/");
        mListener = ref.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot snapshot) {
                if (snapshot.exists()) {
                    System.out.println("The value is now "+snapshot.getValue());

## ChatMessage.java
package com.google.firebase.zerotoapp;

public class ChatMessage {
    public String name;
    public String message;

    public ChatMessage() {
    }

    public ChatMessage(String name, String message) {

## index.html
<html>
<head>
<script src="https://www.gstatic.com/firebasejs/3.0.0/firebase.js"></script>
<title>ZeroToApp</title>
<style>
  #messages { width: 40em; border: 1px solid grey; min-height: 20em; }
  #messages img { max-width: 240px; max-height: 160px; display: block; }
  #header { position: fixed; top: 0; background-color: white; }
  .push { margin-bottom: 2em; }
  @keyframes yellow-fade { 0% {background: #f2f2b8;} 100% {background: none;} }

## README.md

      
              3 files
            
          
              9 forks
            
          
              25 comments
            
          
              47 stars
            
          
                puf
                / README.md
            
            
              Last active
              March 28, 2023 16:37
            
              
                Firebase Hosting Deploy Single File
              
          
    This script may no longer work. Have a look at its (more official) replacement: https://github.com/firebase/firebase-tools/tree/master/scripts/examples/hosting/update-single-file

Firebase Hosting Deploy Single File

This utility script deploy a single local file to an existing Firebase Hosting site.
Other files that are already deployed are left unmodified.
The difference with firebase deploy is that this script does not require you to have a local snapshot of all hosted files,
you just need the one file that you want to add/update.

  
## Detect write errors in Firebase Realtime Database in Android.java
// To detect when a write operation is rejected by your Realtime Database
// security rules, add a completion listener to the `setValue()` call and
// throw the exception if the task failed.
val ref = FirebaseDatabase.getInstance().getReference()
ref.push()
    .setValue(ServerValue.TIMESTAMP)
    .addOnCompleteListener(new CompletionListener() {
      @Override
      public void onComplete(Task<Void> task) {
        Log.i("firebase", String.valueOf(task.isSuccessful()))

## Listen for authentication state.java
// In Firebase it is often better to *react* to authentication state
// changes, instead getting the current authentication state everywhere.
// To respond to auth state changes, use an auth state change listener
// like this:
FirebaseAuth auth = FirebaseAuth.getInstance();
auth.addAuthStateListener(new FirebaseAuth.AuthStateListener() {
    @Override
    public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
        if (firebaseAuth.getCurrentUser() == null) {
            Log.i("firebase", "AuthState changed to null");
	public class Main {
	static ValueEventListener mListener;

	public static void main(String[] args) throws Exception {
	Firebase ref = new Firebase("https://<your-app>.firebaseio.com/");
	mListener = ref.addValueEventListener(new ValueEventListener() {
	@Override
	public void onDataChange(DataSnapshot snapshot) {
	if (snapshot.exists()) {
	System.out.println("The value is now "+snapshot.getValue());
	package com.google.firebase.zerotoapp;

	public class ChatMessage {
	public String name;
	public String message;

	public ChatMessage() {
	}

	public ChatMessage(String name, String message) {
	<html>
	<head>
	<script src="https://www.gstatic.com/firebasejs/3.0.0/firebase.js"></script>
	<title>ZeroToApp</title>
	<style>
	#messages { width: 40em; border: 1px solid grey; min-height: 20em; }
	#messages img { max-width: 240px; max-height: 160px; display: block; }
	#header { position: fixed; top: 0; background-color: white; }
	.push { margin-bottom: 2em; }
	@keyframes yellow-fade { 0% {background: #f2f2b8;} 100% {background: none;} }
	// To detect when a write operation is rejected by your Realtime Database
	// security rules, add a completion listener to the `setValue()` call and
	// throw the exception if the task failed.
	val ref = FirebaseDatabase.getInstance().getReference()
	ref.push()
	.setValue(ServerValue.TIMESTAMP)
	.addOnCompleteListener(new CompletionListener() {
	@Override
	public void onComplete(Task<Void> task) {
	Log.i("firebase", String.valueOf(task.isSuccessful()))
	// In Firebase it is often better to react to authentication state
	// changes, instead getting the current authentication state everywhere.
	// To respond to auth state changes, use an auth state change listener
	// like this:
	FirebaseAuth auth = FirebaseAuth.getInstance();
	auth.addAuthStateListener(new FirebaseAuth.AuthStateListener() {
	@Override
	public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
	if (firebaseAuth.getCurrentUser() == null) {
	Log.i("firebase", "AuthState changed to null");