Getting Total Disk Space Available for Android Device

gistfile1.txt

/**
  * Get the total disk space available on this Android Device
  *
  * @return total size (in bytes) that is the total disk space avaialble on the device.
  */
public static long getTotalDiskSpace() {
  StatFs statFs = new StatFs(Environment.getRootDirectory().getAbsolutePath());
  long totalDiskSpace = statFs.getBlockCount() * statFs.getBlockSize();
  return totalDiskSpace;
}

This code worked for me, but im still looking for an implementation that works on old versions

fun getTotalStorageSize(context: Context): Double {
    val storageManager = context.getSystemService(Context.STORAGE_SERVICE) as StorageManager
       return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
           try {
               val storageStatsManager = context.getSystemService(Context.STORAGE_STATS_SERVICE) as StorageStatsManager
               val uuid = storageManager.getUuidForPath(Environment.getDataDirectory())
               val totalBytes = storageStatsManager.getTotalBytes(uuid)
               val sizeRepresentation = StorageUtil.getStorageSizeRepresentation(totalBytes)
               val base = sizeRepresentation.base.toDouble()
               val totalGB = totalBytes / (base * base * base)
               totalGB
           } catch (e: IOException){
               0.0
           }

        } else {
            TODO("Implementation for devices that work on lower versions")
        }
}

object StorageUtil {
    /**
     * Determines if the data size is in Binary or in Decimal.
     */
    fun getStorageSizeRepresentation(storageSizeInBytes: Long): SizeRepresentation {
        /**
         * In Binary representation the base is 2 and the storage size could be 2, 4, 8, 16, 32, 64, 128, ...
         * In Decimal representation we multiply by 10
         * To determine what type of representation the device uses we can convert the total storage size in bytes to Binary by dividing it on 1024 three times
         * Then we take Log(binary_size) of base 2, if the reminder = 0 then we know we have Binary representation.
         */
        return if (log(storageSizeInBytes / (1024.0.pow(3)), 2.0) % 1.0 == 0.0) {
            SizeRepresentation.Binary
        } else {
            SizeRepresentation.Decimal
        }
    }
}

enum class SizeRepresentation(val base: Int) {
    Binary(1024), Decimal(1000)
}

StatFs ? to root storage . . .

// Get StatFs for the root storage
StatFs statFs = new StatFs(Environment.getRootDirectory().getPath());

// Get StatFs for the external storage
StatFs statFs = new StatFs(Environment.getExternalStorageDirectory().getPath());

Root Storage (Environment.getRootDirectory().getPath()):

• Definition: This refers to the root directory of the Android system. It's where the system files are stored.
• Usage: As a developer, you generally don't need to interact with this directory, since modifying system files can harm the device's stability and integrity.
• Path Example: Typically something like /system.

External Storage (Environment.getExternalStorageDirectory().getPath()):

• Definition: This refers to the primary shared/external storage directory where users can store their media and files. It's accessible by both the user and apps, and is often what people refer to as the "SD card" (though it may be internal to the device).
• Usage: You use this directory to store user data that needs to be shared across apps or that users might want to access directly (e.g., pictures, videos, downloads).
• Path Example: Typically something like /storage/emulated/0.

Storage Type	Access Method	Typical Path	Usage
Root Storage	Environment.getRootDirectory().getPath()	/system	System files, not usually modified by apps
External Storage (Phone: default storage available for user)	Environment.getExternalStorageDirectory().getPath()	/storage/emulated/0	User files, media, shared app data
External Storage (SDCard)	Environment.getExternalStorageDirectory().getPath()	/storage/emulated/1	User files, media in MicroSD card

i was commenting @mohammednawas8

for below Build.VERSION_CODES.O