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audio - Play sound on button click android

How do I get a button to play a sound from raw when click? I just created a button with id button1, but whatever code I write, all is wrong.

import android.media.MediaPlayer;

public class BasicScreenActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_basic_screen);
    }

    Button one = (Button)this.findViewById(R.id.button1);
    MediaPlayer = mp;
    mp = MediaPlayer.create(this, R.raw.soho);
    zero.setOnCliclListener(new View.OnClickListener() )

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.basic_screen, menu);
        return true;
    }



}
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1 Answer

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by (71.8m points)

This is the most important part in the code provided in the original post.

Button one = (Button) this.findViewById(R.id.button1);
final MediaPlayer mp = MediaPlayer.create(this, R.raw.soho);
one.setOnClickListener(new OnClickListener(){

    public void onClick(View v) {
        mp.start();
    }
});

To explain it step by step:

Button one = (Button) this.findViewById(R.id.button1);

First is the initialization of the button to be used in playing the sound. We use the Activity's findViewById, passing the Id we assigned to it (in this example's case: R.id.button1), to get the button that we need. We cast it as a Button so that it is easy to assign it to the variable one that we are initializing. Explaining more of how this works is out of scope for this answer. This gives a brief insight on how it works.

final MediaPlayer mp = MediaPlayer.create(this, R.raw.soho);

This is how to initialize a MediaPlayer. The MediaPlayer follows the Static Factory Method Design Pattern. To get an instance, we call its create() method and pass it the context and the resource Id of the sound we want to play, in this case R.raw.soho. We declare it as final. Jon Skeet provided a great explanation on why we do so here.

one.setOnClickListener(new OnClickListener(){

    public void onClick(View v) {
        //code
    }
});

Finally, we set what our previously initialized button will do. Play a sound on button click! To do this, we set the OnClickListener of our button one. Inside is only one method, onClick() which contains what instructions the button should do on click.

public void onClick(View v) {
    mp.start();
}

To play the sound, we call MediaPlayer's start() method. This method starts the playback of the sound.

There, you can now play a sound on button click in Android!


Bonus part:

As noted in the comment belowThanks Langusten Gustel!, and as recommended in the Android Developer Reference, it is important to call the release() method to free up resources that will no longer be used. Usually, this is done once the sound to be played has completed playing. To do so, we add an OnCompletionListener to our mp like so:

mp.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
    public void onCompletion(MediaPlayer mp) {
        //code
    }
});

Inside the onCompletion method, we release it like so:

public void onCompletion(MediaPlayer mp) {
    mp.release();
}

There are obviously better ways of implementing this. For example, you can make the MediaPlayer a class variable and handle its lifecycle along with the lifecycle of the Fragment or Activity that uses it. However, this is a topic for another question. To keep the scope of this answer small, I wrote it just to illustrate how to play a sound on button click in Android.


Original Post

First. You should put your statements inside a block, and in this case the onCreate method.

Second. You initialized the button as variable one, then you used a variable zero and set its onClickListener to an incomplete onClickListener. Use the variable one for the setOnClickListener.

Third, put the logic to play the sound inside the onClick.

In summary:

import android.app.Activity;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class BasicScreenActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {        
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_basic_screen);

        Button one = (Button)this.findViewById(R.id.button1);
        final MediaPlayer mp = MediaPlayer.create(this, R.raw.soho);
        one.setOnClickListener(new OnClickListener(){

            public void onClick(View v) {
                mp.start();
            }
        });
    }
}

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