Monday, December 13, 2010

Implement a SeekBar to control the volume of Video Player

Modify the former exercise "Play 3gp video file using MediaPlayer" to add a SeekBar to control the volume.



In order to create a volume control using SeekBar, we have to know the maximum volume and current volume. It can be retrieved using the method audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC) and audioManager.getStreamVolume(AudioManager.STREAM_MUSIC). And we can change the volume when SeekBar changed, using the method audioManager.setStreamVolume(AudioManager.STREAM_MUSIC, volume index, flags).

Firstly, modify main.xml to add a SeekBar as Volume Control.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>
<LinearLayout
android:orientation="horizontal"
android:layout_height="wrap_content"
android:layout_width="fill_parent"
>
<Button
android:id="@+id/playvideoplayer"
android:layout_width="0dip"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="- PLAY Video -"
/>
<Button
android:id="@+id/pausevideoplayer"
android:layout_width="0dip"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="- PAUSE Video -"
/>
</LinearLayout>
<SeekBar
android:id="@+id/volbar"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_margin="10px"
/>
<SurfaceView
android:id="@+id/surfaceview"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>


Modify AndroidVideoPlayer to handle the SeekBar as Volume Control.
package com.exercise.AndroidVideoPlayer;

import java.io.IOException;

import android.app.Activity;
import android.content.Context;
import android.graphics.PixelFormat;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;
import android.widget.SeekBar;

public class AndroidVideoPlayer extends Activity implements SurfaceHolder.Callback{

MediaPlayer mediaPlayer;
SurfaceView surfaceView;
SurfaceHolder surfaceHolder;
boolean pausing = false;

AudioManager audioManager;

String stringPath = "/sdcard/samplevideo.3gp";

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);


audioManager = (AudioManager)getSystemService(Context.AUDIO_SERVICE);
int maxVolume = audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
int curVolume = audioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
SeekBar volControl = (SeekBar)findViewById(R.id.volbar);
volControl.setMax(maxVolume);
volControl.setProgress(curVolume);
volControl.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {

@Override
public void onStopTrackingTouch(SeekBar arg0) {
// TODO Auto-generated method stub

}

@Override
public void onStartTrackingTouch(SeekBar arg0) {
// TODO Auto-generated method stub

}

@Override
public void onProgressChanged(SeekBar arg0, int arg1, boolean arg2) {
// TODO Auto-generated method stub
audioManager.setStreamVolume(AudioManager.STREAM_MUSIC, arg1, 0);
}
});


Button buttonPlayVideo = (Button)findViewById(R.id.playvideoplayer);
Button buttonPauseVideo = (Button)findViewById(R.id.pausevideoplayer);

getWindow().setFormat(PixelFormat.UNKNOWN);
surfaceView = (SurfaceView)findViewById(R.id.surfaceview);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);
surfaceHolder.setFixedSize(176, 144);
surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
mediaPlayer = new MediaPlayer();

buttonPlayVideo.setOnClickListener(new Button.OnClickListener(){

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
pausing = false;

if(mediaPlayer.isPlaying()){
mediaPlayer.reset();
}

mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
mediaPlayer.setDisplay(surfaceHolder);

try {
mediaPlayer.setDataSource(stringPath);
mediaPlayer.prepare();
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

mediaPlayer.start();


}});

buttonPauseVideo.setOnClickListener(new Button.OnClickListener(){

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(pausing){
pausing = false;
mediaPlayer.start();
}
else{
pausing = true;
mediaPlayer.pause();
}
}});

}



@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
// TODO Auto-generated method stub

}

@Override
public void surfaceCreated(SurfaceHolder holder) {
// TODO Auto-generated method stub

}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
// TODO Auto-generated method stub

}
}


Download the files.

8 comments:

Igor said...

thank you very much.
This is really sweet!

sathya said...

Hi ,
Thanks for your great work.
It is working for me in development of MediaPlayer appliction to play audio files. The volume control also working fine for me.
But when i start touching seekBar to control volume the default volume notification alert box also displaying on the screen.
How can i disable that default notification if i use my own seekbar to change media volume?

Thanks in advance
s.avunoori

Android Er said...

hello sathya,

Ooop! It's the most difficult issue! I have no this problem on WildFire.

Can I know which device you use?

Nick said...

Your examples are fantastic! Just want you to know how helpful they are. I would love a digital alarm clock example! Thank you again

3z0ru$ said...

Hey, nice tutorial! Is there any way to remove the background of the seekbar so that the seekbar appears on top of the video? I tried volControl.setBackgroundDrawable(null) but its doesn't do anything.

Android Er said...

hello 3z0ru$,

Please check Example of FrameLayout

Paladugula said...

hi,

i want to play all the Video files with .3gp extension,what changes to be done in your code???

JayC said...

Excellent. Thanks.