How to Fetch Currently Running Tasks in Android Programmatically?

Last Updated : 23 Jan, 2022

Android devices run several tasks in the background for providing a seamless experience to the users. Importantly, tracking background and foreground usages is important as it directly impacts the battery life and static memory, i.e. RAM. One can enable the developer option in the settings to track all the background tasks and services. However, one can even programmatically find out the same. So in this article, we will show you how you could programmatically fetch currently running tasks in Android. Follow the below steps once the IDE is ready.

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. We demonstrated the application in Kotlin, so make sure you select Kotlin as the primary language while creating a New Project.

Step 2: Working with the activity_main.xml file

Navigate to the app > res > layout > activity_main.xml and add the below code to that file. Below is the code for the activity_main.xml file. We added a TextView to display the list of running tasks.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
    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">

    <TextView
        android:id="@+id/text_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scrollbars="vertical"/>

</RelativeLayout>

Step 3: 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. In the main code, primarily, we shall be using the ActivityManager to get the list of running tasks.

package org.geeksforgeeks.currentlyrunningapps

import android.app.ActivityManager
import android.content.Context
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.TextView
import java.util.*

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        // Declaring and initializing the 
        // TextView from the layout file
        val mTextView = findViewById<TextView>(R.id.text_view)
        
        // Getting the instance of ActivityManager
        val mActivityManager = getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager
        
        // Getting the tasks in the form of a list
        val mRecentTasks: List<ActivityManager.RunningTaskInfo> = Objects.requireNonNull(mActivityManager).getRunningTasks(Int.MAX_VALUE)

        var mString = ""

        // Creating a string of each index of the list
        for (i in mRecentTasks.indices){
            mString = mString + " " + mRecentTasks[i].baseActivity?.toShortString() + " " + mRecentTasks[i].id + "\n\n"
        }

        // Setting the TextView with the string
        mTextView.text = mString
    }
}