Android Jetpack Compose – Retrieve Image From Firebase in Realtime

When we are creating an android app then instead of inserting an image manually we want to get that from the internet and using this process the app size will become less. So, using firebase we can do this. We can create our storage bucket and we can insert our image there and get it directly into our app. But what if we want to change that image and instead of that image we want to insert the new one then for doing this we have to change our code but here our solution comes we can get that image in realtime in our app using real-time database then we can change that image from firebase and in real-time, our app image will also change we don’t have to do changes in our code. In this article, we will take a look at How to retrieve images from the Firebase Realtime database in Android using Jetpack Compose. 

Step by Step Implementation

Step 1: Create a New Project in Android Studio

To create a new project in Android Studio please refer to How to Create/Start a New Project in Android Studio. While choosing the template, select Empty Compose Activity. If you do not find this template, try upgrading the Android Studio to the latest version. We demonstrated the application in Kotlin, so make sure you select Kotlin as the primary language while creating a New Project.

Step 2: Connect your app to Firebase

After creating a new project, navigate to the Tools option on the top bar. Inside that click on Firebase. After clicking on Firebase, you can get to see the right column mentioned below in the screenshot.  

Inside that column Navigate to Firebase Realtime Database. Click on that option and you will get to see two options on Connect app to Firebase and Add Firebase Realtime Database to your app. Click on Connect now and your app will be connected to Firebase. After that click on the second option and now your App is connected to Firebase.

After completing this process you will get to see the below screen.

Now verify whether your app is connected to Firebase or not. Go to your build.gradle file. Navigate to the app > Gradle Scripts > build.gradle file and make sure that the below dependency is added in your dependencies section.

implementation platform('com.google.firebase:firebase-bom:30.3.2')
 implementation 'com.google.firebase:firebase-database-ktx'
 // added dependency below to load image from URL 
     implementation("io.coil-kt:coil-compose:2.0.0-rc01")

If the above dependency is not added to your dependencies section. Add this dependency and sync your project.

Step 3: Add internet permission to your AndroidManifest.xml file

Add the permission for the internet in the AndroidManifest.xml file. 

XML

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Step 4: Working with the MainActivity.kt file

Go to the MainActivity.kt file and refer to the following code. Below is the code for the MainActivity.java file. Comments are added inside the code to understand the code in more detail.

Kotlin

package com.example.firebaseproject

import android.annotation.SuppressLint
import android.content.Context
import android.os.Bundle
import android.widget.Toast
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.Image
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.*
import androidx.compose.material.*
import androidx.compose.runtime.*
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.platform.LocalContext
import androidx.compose.ui.text.TextStyle
import androidx.compose.ui.text.font.FontFamily
import androidx.compose.ui.text.font.FontStyle
import androidx.compose.ui.text.font.FontWeight
import androidx.compose.ui.text.input.TextFieldValue
import androidx.compose.ui.text.style.TextAlign
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.sp
import coil.compose.rememberAsyncImagePainter
import com.example.firebaseproject.ui.theme.FirebaseProjectTheme
import com.example.firebaseproject.ui.theme.greenColor
import com.google.firebase.database.*


class MainActivity : ComponentActivity() {
    @SuppressLint("UnrememberedMutableState")
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            FirebaseProjectTheme {
                // A surface container using the 'background' color from the theme
                Surface(
                    // on below line we are specifying modifier and color for our app
                    modifier = Modifier.fillMaxSize(), color = MaterialTheme.colors.background
                ) {
                    // on the below line we are specifying
                    // the theme as the scaffold.
                    Scaffold(
                        // in scaffold we are
                        // specifying the top bar.
                        topBar = {
                            // inside top bar we are
                            // specifying background color.
                            TopAppBar(backgroundColor = greenColor,
                                // along with that we are specifying
                                // title for our top bar.
                                title = {
                                    // in the top bar we are
                                    // specifying title as a text
                                    Text(
                                        // on below line we are specifying
                                        // text to display in top app bar
                                        text = "GFG",
                                        // on below line we are specifying
                                        // modifier to fill max width
                                        modifier = Modifier.fillMaxWidth(),
                                        // on below line we are
                                        // specifying text alignment
                                        textAlign = TextAlign.Center,
                                        // on below line we are specifying
                                        // color for our text.
                                        color = Color.White
                                    )
                                })
                        }) {
                        // on below line we are calling
                        // method to display UI
                        firebaseUI(LocalContext.current)
                    }
                }
            }
        }
    }
}

@Composable
fun firebaseUI(context: Context) {

    // on below line creating
    // variable for message.
    val message = remember {
        mutableStateOf("")
    }
    // on below line creating variable for firebase
    // database and database reference.
    val firebaseDatabase = FirebaseDatabase.getInstance();
    val databaseReference = firebaseDatabase.getReference("Data");

    // on below line adding value event listener for database reference.
    databaseReference.addValueEventListener(object : ValueEventListener {
        override fun onDataChange(snapshot: DataSnapshot) {
            // this method is call to get the realtime
            // updates in the data.
            // this method is called when the data is
            // changed in our Firebase console.
            // below line is for getting the data from
            // snapshot of our database.
            val value = snapshot.getValue(String::class.java)

            // after getting the value we are setting
            // our value to message.
            message.value = value!!
        }

        override fun onCancelled(error: DatabaseError) {
            // calling on cancelled method when we receive
            // any error or we are not able to get the data.
            Toast.makeText(context, "Fail to get data.", Toast.LENGTH_SHORT).show()
        }
    })

    // on below line creating a column
    // to display our retrieved image view.
    Column(
        // adding modifier for our column
        modifier = Modifier
            .fillMaxHeight()
            .fillMaxWidth()
            .background(Color.White),
        // on below line adding vertical and
        // horizontal alignment for column.
        verticalArrangement = Arrangement.Center, horizontalAlignment = Alignment.CenterHorizontally
    ) {
        // on below line we are creating an image
        Image(
            // on below line we are adding the image url
            // from which we will  be loading our image.
            painter = rememberAsyncImagePainter(message.value),

            // on below line we are adding content
            // description for our image.
            contentDescription = "gfg image",

            // on below line we are adding modifier for our
            // image as wrap content for height and width.
            modifier = Modifier
                .wrapContentSize()
                .wrapContentHeight()
                .wrapContentWidth()
        )
    }
}

After adding this code to your app. Now go to Firebase and click on Go to console option which is in the top right corner.  

 After clicking on this screen you will get to see the below screen with your all project inside that select your project.  

Inside that screen click n Realtime Database in the left window.  

After clicking on this option you will get to see the screen on the right side. On this page click on the Rules option which is present in the top bar. You will get to see the below screen.

In this project, we are adding our rules as true for reading as well as a write because we are not using any authentication to verify our user. So we are currently setting it to true to test our application. After changing your rules. Click on the publish button at the top right corner and your rules will be saved there. Now again come back to the Data tab. Now we will be adding our data to Firebase manually from Firebase itself. Now again come back to the Data tab. Now we will be adding our data to Firebase manually from Firebase itself.

Step 5: Adding URL for your Image in Firebase Console

Inside Firebase Realtime Database. Navigate to the Data tab. Inside this tab Hower on the database section inside click on the “+” icon. After clicking on the “+” icon you will get to see two input fields which are the Name and Value fields. Inside the Name field, you have to add a reference for your image file which in our case is “URL”. And in our value field, we have to add a URL for our image file. After adding the value in this field. Click on Add button and your data will be added to Firebase Console. After adding the URL for your video. Now run your app and see the output of the app below :

Output:

You can change the URL of your image dynamically from the database and the image will be updated inside the application in real-time.