Services in Android using Jetpack Compose

Services in Android applications are used to perform some background tasks within android applications. We can call the service to perform a specific task in the background of our application. That task will be performed continuously if our application is not visible to the user. Services are generally seen used in Music Player applications where the songs are played in the background and simultaneously we will be able to use other applications as well. In this article, we will take a look at How to use Services 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: Adding a new color to the Color.kt file

Navigate to app > java > your app’s package name > ui.theme > Color.kt file and add the below code to it. Comments are added in the code to get to know in detail. 

Kotlin

package com.example.newcanaryproject.ui.theme

import androidx.compose.ui.graphics.Color

val Purple200 = Color(0xFF0F9D58)
val Purple500 = Color(0xFF0F9D58)
val Purple700 = Color(0xFF3700B3)
val Teal200 = Color(0xFF03DAC5)

// on below line we are adding different colors.
val greenColor = Color(0xFF0F9D58)

Step 3: Creating a new class for our service

Navigate to app>java>your app’s package name>Right click on it>New>Java/Kotlin class and name it as MyService and add the below code to it. Comments are added in the code to get to know in detail. 

Kotlin

package com.example.newcanaryproject

import android.app.Service
import android.content.Intent
import android.media.MediaPlayer
import android.os.IBinder
import android.provider.Settings

class MyService : Service() {
    // declaring object of MediaPlayer
    private lateinit var player: MediaPlayer

    // execution of service will start
    // on calling this method
    override fun onStartCommand(intent: Intent, flags: Int, startId: Int): Int {

        // creating a media player which
        // will play the audio of Default
        // ringtone in android device
        player = MediaPlayer.create(this, Settings.System.DEFAULT_RINGTONE_URI)

        // providing the boolean
        // value as true to play
        // the audio on loop
        player.setLooping(true)

        // starting the process
        player.start()

        // returns the status
        // of the program
        return START_STICKY
    }

    // execution of the service will
    // stop on calling this method
    override fun onDestroy() {
        super.onDestroy()

        // stopping the process
        player.stop()
    }

    override fun onBind(intent: Intent): IBinder? {
        return null
    }
}

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.kt file. Comments are added inside the code to understand the code in more detail.

Kotlin

package com.example.newcanaryproject

import android.content.Context
import android.content.Context.BATTERY_SERVICE
import android.content.Intent
import android.graphics.drawable.Animatable
import android.net.wifi.WifiManager
import android.text.format.Formatter
import android.os.BatteryManager
import android.os.Build
import android.os.Bundle
import android.provider.Settings
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.annotation.RequiresApi
import androidx.compose.animation.core.LinearOutSlowInEasing
import androidx.compose.animation.core.RepeatMode
import androidx.compose.animation.core.infiniteRepeatable
import androidx.compose.animation.core.keyframes
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.shape.CircleShape
import androidx.compose.material.*
import androidx.compose.runtime.Composable
import androidx.compose.runtime.LaunchedEffect
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.graphics.graphicsLayer
import androidx.compose.ui.platform.LocalContext
import androidx.compose.ui.platform.LocalDensity
import androidx.compose.ui.text.font.FontWeight
import androidx.compose.ui.text.style.TextAlign
import androidx.compose.ui.unit.Dp
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.sp
import com.example.newcanaryproject.ui.theme.NewCanaryProjectTheme
import com.example.newcanaryproject.ui.theme.greenColor
import com.github.skydoves.colorpicker.compose.*
import kotlinx.coroutines.delay

class MainActivity : ComponentActivity() {

    @RequiresApi(Build.VERSION_CODES.M)
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            NewCanaryProjectTheme {
                // on below line we are specifying background color for our application
                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 tile 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 connection
                          // information method to display UI
                        servicesUI(context = LocalContext.current)
                    }
                }
            }
        }
    }
}

@Composable
fun servicesUI(context: Context) {
    // on below line creating variable
    // for service status and button value.
    val serviceStatus = remember {
        mutableStateOf(false)
    }
    val buttonValue = remember {
        mutableStateOf("Start Service")
    }

    // on below line we are creating a column,
    Column(
        // on below line we are adding a modifier to it,
        modifier = Modifier
            .fillMaxSize()
            // on below line we are adding a padding.
            .padding(all = 30.dp),
        horizontalAlignment = Alignment.CenterHorizontally,
        verticalArrangement = Arrangement.Center,
    ) {
        // on the below line we are adding a text for heading.
        Text(
            // on below line we are specifying text
            text = "Services in Android",
            // on below line we are specifying text color,
            // font size and font weight
            color = greenColor,
            fontSize = 20.sp,
            fontWeight = FontWeight.Bold
        )

        Spacer(modifier = Modifier.height(20.dp))
        Button(onClick = {
            if (serviceStatus.value) {
                // service already running
                // stop the service
                serviceStatus.value = !serviceStatus.value
                buttonValue.value = "Start Service"
                context.stopService(Intent(context, MyService::class.java))

            } else {
                // service not running start service.
                serviceStatus.value = !serviceStatus.value
                buttonValue.value = "Stop Service"

                // starting the service
                context.startService(Intent(context, MyService::class.java))
            }

        }) {
            // on below line creating a text for our button.
            Text(
                // on below line adding a text,
                // padding, color and font size.
                text = buttonValue.value,
                modifier = Modifier.padding(10.dp),
                color = Color.White,
                fontSize = 20.sp
            )
        }
    }
}

Step 5: Adding our service to our AndroidManifest.xml file

Navigate to the AndroidManifest.xml file and add below to your activity tag to register your service. 

XML

<service android:name=".MyService" />

Now run your project to see the output of your application. 

Output: