Android firebase database
Firebase cloud storage is the best option to make a app on android firebase realtime database for the beginners.There is no server side script involved in this process so on any basis its simple and easier to start.
Making use of firebase services is advisory as its providing a free service based on the usage* and is providing a efficient and reliable service so i recommend you to choose it when there is suitable requirement for you not only database firebase offer ‘s various service which you can find here.
Also you can find the relevant video tutorials to get more in-depth knowledge regarding the topic we are dealing with.
We will provide the complete details in this blog and also video tutorials provided for the easier understanding.
Android firebase database video tutorial :
If you are facing any trouble in adding firebase to your account may refer to
Project Structure :
The project structure of android firebase database is shown in this image.
Dependency :
Make sure you find the latest version of dependency’s before proceeding further to avoid deprecated classes and thereby errors.
build.gradle (Project: FirebaseDatabase)
classpath 'com.google.gms:google-services:4.2.0'
build.gradle (Module: App)
apply plugin: 'com.google.gms.google-services'
implementation 'com.google.firebase:firebase-database-ktx:19.3.0'
Rules :
I have made rules public just for this tutorial you may make them private
{
"rules": {
".read": true,
".write": true
}
}
for private, default, user rules refer
activity_main.xml
Add a edittext, button and text view to display fetched data.
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<EditText
android:id="@+id/edt_input"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="50dp"
android:hint="message"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="@+id/btn_submit"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="48dp"
android:text="submit"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.755"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/edt_input" />
<TextView
android:id="@+id/txt_display"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World!"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
MainActivity.class
Create an object for android firebase database reference
lateinit var myRef : DatabaseReference
database object
val database = Firebase.database
setting key for data
myRef = database.getReference("message")
setting value for the key
myRef.setValue("Androidcoding.in")
Can find the screen below showing the data inserted using key value attributes in android firebase database.
listener to handle task success and failure states
myRef.addValueEventListener(object : ValueEventListener {
override fun onDataChange(dataSnapshot: DataSnapshot) {
// This method is called once with the initial value and again
// whenever data at this location is updated.
val value = dataSnapshot.getValue()
txt_display.setText("Value is: $value")
}
override fun onCancelled(error: DatabaseError) {
// Failed to read value
Log.w("Status", "Failed to read value.", error.toException())
}
})
For better practice use view binding’s may find more information here
import android.os.Bundle
import android.util.Log
import android.view.View
import androidx.appcompat.app.AppCompatActivity
import com.google.firebase.database.DataSnapshot
import com.google.firebase.database.DatabaseError
import com.google.firebase.database.DatabaseReference
import com.google.firebase.database.ValueEventListener
import com.google.firebase.database.ktx.database
import com.google.firebase.ktx.Firebase
import kotlinx.android.synthetic.main.activity_main.*
class MainActivity : AppCompatActivity() ,View.OnClickListener{
lateinit var myRef : DatabaseReference
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// Write a message to the database
val database = Firebase.database
myRef = database.getReference("message")
myRef.setValue("Androidcoding.in")
btn_submit.setOnClickListener(this)
// Read from the database
myRef.addValueEventListener(object : ValueEventListener {
override fun onDataChange(dataSnapshot: DataSnapshot) {
// This method is called once with the initial value and again
// whenever data at this location is updated.
val value = dataSnapshot.getValue()
txt_display.setText("Value is: $value")
}
override fun onCancelled(error: DatabaseError) {
// Failed to read value
Log.w("Status", "Failed to read value.", error.toException())
}
})
}
override fun onClick(v: View?) {
when(v!!.id){
R.id.btn_submit -> {
myRef.setValue(edt_input.text.toString())
}
}
}
}
Android firebase database output :
The screen depicts android firebase database
If there are any query’s in this tutorial on android firebase database do let us know in the comment section below and also like share this tutorial to get more interesting updates.
