Services in Android using Jetpack Compose

Last Updated : 31 Aug, 2022

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 
            ) 
        } 
    } 
}