Kotlin Android Media Player

MediaPlayer is a class that is used to control the playback of audio/video files and streams.

The android.media.MediaPlayer class is used to control the audio or video files. It accesses the built-in media player services such as playing audio, video, etc. To use the MediaPlayer class, we have to call the create the instance of it by calling the create() method of this class.

Methods of MediaPlayer class

There are several methods of MediaPlayer class available. Some of them are as follows:

Method	Description
public void setDataSource(String path)	It sets the data source (file path or http url) to use.
public void prepare()	It prepares the player for playback synchronously.
public void start()	It starts or resumes the playback.
public void stop()	It stops the playback.
public void pause()	It pauses the playback.
public boolean isPlaying()	It checks if the media player is playing.
public void seekTo(int millis)	It seeks to specified time in milliseconds.
public void setLooping(boolean looping)	It sets the player for looping or non-looping.
public boolean isLooping()	It checks if the player is looping or non-looping.
public void selectTrack(int index)	It selects a track for the specified index.
public int getCurrentPosition()	It returns the current playback position.
public int getDuration()	It returns duration of the file.
public void setVolume(float leftVolume,float rightVolume)	It sets the volume on this player.

Example of Android MediaPlayer with SeekBar

In this example, we will create a Media Player with playback control functionality such as play, pause, and stop. We also integrate the SeekBar to show the progress level of the media player.

activity_main.xml

In the activity_main.xml layout file, we add the Buttons to control media playback, TextView to display the time duration of song and SeekBar to show the progress level of the media file.

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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="example.javatpoint.com.kotlinmediaplayer.MainActivity">

    <Button
        android:id="@+id/pauseBtn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:enabled="false"
        android:text="Pause"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toStartOf="@+id/playBtn"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/playBtn"
        android:layout_width="88dp"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:text="Play"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toStartOf="@+id/stopBtn"
        app:layout_constraintStart_toEndOf="@+id/pauseBtn"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/stopBtn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="24dp"
        android:layout_marginRight="24dp"
        android:layout_marginTop="8dp"
        android:enabled="false"
        android:text="Stop"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <RelativeLayout
        android:layout_width="368dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="76dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="1.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <TextView
            android:id="@+id/tv_pass"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

        <TextView
            android:id="@+id/tv_due"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentEnd="true"
            android:layout_alignParentRight="true" />

        <SeekBar
            android:id="@+id/seek_bar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@id/tv_pass"
            android:saveEnabled="false" />
    </RelativeLayout>
</android.support.constraint.ConstraintLayout>

MianActivity.kt

The instance of MediaPlayer class is created using the MediaPlayer.create() method. In this example, we are reading the media file from the raw directory. The MediaPlayer.start() method starts playing media file, MediaPlayer.pause() method pause media and Media.stop() method stops playing media file.

package example.javatpoint.com.kotlinmediaplayer

import android.media.MediaPlayer
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.widget.Toast
import kotlinx.android.synthetic.main.activity_main.*
import android.os.Handler
import android.widget.SeekBar

class MainActivity : AppCompatActivity() {

    private lateinit var mediaPlayer: MediaPlayer
    private lateinit var runnable:Runnable
    private var handler: Handler = Handler()
    private var pause:Boolean = false
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        // Start the media player
        playBtn.setOnClickListener{
            if(pause){
                mediaPlayer.seekTo(mediaPlayer.currentPosition)
                mediaPlayer.start()
                pause = false
                Toast.makeText(this,"media playing",Toast.LENGTH_SHORT).show()
            }else{

                mediaPlayer = MediaPlayer.create(applicationContext,R.raw.school_bell)
                mediaPlayer.start()
                Toast.makeText(this,"media playing",Toast.LENGTH_SHORT).show()

            }
            initializeSeekBar()
            playBtn.isEnabled = false
            pauseBtn.isEnabled = true
            stopBtn.isEnabled = true

            mediaPlayer.setOnCompletionListener {
                playBtn.isEnabled = true
                pauseBtn.isEnabled = false
                stopBtn.isEnabled = false
                Toast.makeText(this,"end",Toast.LENGTH_SHORT).show()
            }
        }
        // Pause the media player
        pauseBtn.setOnClickListener {
            if(mediaPlayer.isPlaying){
                mediaPlayer.pause()
                pause = true
                playBtn.isEnabled = true
                pauseBtn.isEnabled = false
                stopBtn.isEnabled = true
                Toast.makeText(this,"media pause",Toast.LENGTH_SHORT).show()
            }
        }
        // Stop the media player
        stopBtn.setOnClickListener{
            if(mediaPlayer.isPlaying || pause.equals(true)){
                pause = false
                seek_bar.setProgress(0)
                mediaPlayer.stop()
                mediaPlayer.reset()
                mediaPlayer.release()
                handler.removeCallbacks(runnable)

                playBtn.isEnabled = true
                pauseBtn.isEnabled = false
                stopBtn.isEnabled = false
                tv_pass.text = ""
                tv_due.text = ""
                Toast.makeText(this,"media stop",Toast.LENGTH_SHORT).show()
            }
        }
        // Seek bar change listener
        seek_bar.setOnSeekBarChangeListener(object : SeekBar.OnSeekBarChangeListener {
            override fun onProgressChanged(seekBar: SeekBar, i: Int, b: Boolean) {
                if (b) {
                    mediaPlayer.seekTo(i * 1000)
                }
            }

            override fun onStartTrackingTouch(seekBar: SeekBar) {
            }

            override fun onStopTrackingTouch(seekBar: SeekBar) {
            }
        })
    }
    // Method to initialize seek bar and audio stats
    private fun initializeSeekBar() {
        seek_bar.max = mediaPlayer.seconds

        runnable = Runnable {
            seek_bar.progress = mediaPlayer.currentSeconds

            tv_pass.text = "${mediaPlayer.currentSeconds} sec"
            val diff = mediaPlayer.seconds - mediaPlayer.currentSeconds
            tv_due.text = "$diff sec"

            handler.postDelayed(runnable, 1000)
        }
        handler.postDelayed(runnable, 1000)
    }
}
// Creating an extension property to get the media player time duration in seconds
val MediaPlayer.seconds:Int
    get() {
        return this.duration / 1000
    }
// Creating an extension property to get media player current position in seconds
val MediaPlayer.currentSeconds:Int
    get() {
        return this.currentPosition/1000
    }

Output: