How to Check if the Battery is Charging or Not in Android Programmatically?

The charging status can change as quickly as a device can be plugged in, so it’s crucial to monitor the charging state for changes and alter your refresh rate accordingly. The BatteryManager broadcasts an action whenever the device is connected or disconnected from power. It is important to receive these events even while the app isn’t running significantly. Such events should impact how often you start the app to initiate a background update. So you should register a BroadcastReceiver in the manifest to listen for both events by defining the ACTION_POWER_CONNECTED and ACTION_POWER_DISCONNECTED within an intent filter (filter). A sample GIF is given below to get an idea about what we are going to do in this article. Note that we are going to implement this project using the Kotlin language. Keep an eye on the battery status in the status bar.

Approach

Step 1: Create a New Project

To create a new project in Android Studio please refer to How to Create/Start a New Project in Android Studio. Note that select Kotlin as the programming language.

Step 2: Working with the activity_main.xml file

Go to the activity_main.xml file, which represents the UI of the project. Add a Button, so whenever the user will click on the Button a Toast message with battery state (charging or not) will be popped up on the screen. Below is the code for the activity_main.xml file.

XML

<?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">

    <Button
        android:id="@+id/btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:text="Click"
        />

</RelativeLayout>

Step 3: Working with the MainActivity.kt file

Finally, go to the MainActivity.kt file, and refer 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

import android.content.Intent
import android.content.IntentFilter
import android.os.BatteryManager
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.widget.Button
import android.widget.Toast

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

        // Button onclick will display the status of charging
        val btn = findViewById<Button>(R.id.btn)

        btn.setOnClickListener {

              // Intent to check the actions on battery
            val batteryStatus: Intent? = IntentFilter(Intent.ACTION_BATTERY_CHANGED).let { ifilter ->
                applicationContext.registerReceiver(null, ifilter)
            }

            // isCharging if true indicates charging is ongoing and vice-versa
            val status: Int = batteryStatus?.getIntExtra(BatteryManager.EXTRA_STATUS, -1) ?: -1
            val isCharging: Boolean = status == BatteryManager.BATTERY_STATUS_CHARGING
                    || status == BatteryManager.BATTERY_STATUS_FULL

              // Display whatever the state in the form of a Toast
            if(isCharging) {
                Toast.makeText(applicationContext, "Charging", Toast.LENGTH_LONG).show()
            } else {
                Toast.makeText(applicationContext,"Not Charging", Toast.LENGTH_LONG).show()
            }
        }
    }
}

Output: Run on Physical Device

Keep an eye on the battery status in the status bar.