Android: How to get app to remember if mute button has been pressed or not

Question

I have successfully created a button that mute my button press sound if wanted. The problem I am having is that when I leave the page or close the app and return sound a returne

Answer 1

In your OnClickListener's onClick method you can save the state

getSharedPreferences("SP", Context.MODE_PRIVATE).edit().putBoolean("mute_pressed", true).commit();

or if you want to save the int value like you are in onPause just do

getSharedPreferences("SP", Context.MODE_PRIVATE).edit().putBoolean("mute_val", Sound).commit();

Because as of right now you aren't actually saving as you increment/decrement you are only saving onPause(). You can then restore that value in onResume() by changing

int counter = ...
// to
Sound =...

This will set your classes Sound variable to the old stored value.

I would also recommend, instead of using "SP" (I highly recommend against using the same key values for your shared preference key and your stored value key while I am at it), to use static variables you set in the top of your class as something like

private final static String PREFS_KEY = "shared_prefs";

then use your variables like

getSharedPreferences(PREFS_KEY, Context.MODE_PRIVATE)...

this helps with localization. You should also check into naming conventions in Java to avoid headaches down the road when things get more complicating.

UPDATED TO WORK WITH YOUR CODE

// this should be HomePage, not homePage
public class homePage extends Activity {

    private final static String PREFS_KEY = "shared_prefs";
    private final static String MUTE_PRESSED_KEY = "mute_pressed";

    private Button Mute;    // this should be mute, not Mute
    private int Sound = 0;  // this should be sound, not Sound
    private SharedPreferences prefs;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.home_page);

        Mute = (Button) findViewById(R.id.mute);
        setButtonOnClickListeners();

        prefs = getSharedPreferences(PREFS_KEY, Context.MODE_PRIVATE);
        if(prefs.getBoolean(MUTE_PRESSED_KEY, false))
            Sound = 1;
        else
            Sound = 0;
    }

    // I DIDN'T REALLY LOOK AT THIS SO COUNTING ON YOU THAT IT WORKS
    public void sound() {
        final MediaPlayer mp = new MediaPlayer();
        if (Sound == 1) {
            try {
                AssetFileDescriptor afd;
                afd = getAssets().openFd("butpress.mp3");
                mp.setDataSource(afd.getFileDescriptor(), afd.getStartOffset(),
                        afd.getLength());
                mp.prepare();
                mp.start();
            } catch (IllegalStateException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        } else if (Sound == 0) {
            mp.stop();
        }
    }

    private void setButtonOnClickListeners() {

        Mute.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                if (Sound == 1) {
                    Mute.setBackgroundResource(R.drawable.sound_off);
                    Sound = 0;
                    prefs.edit().putBoolean(MUTE_PRESSED_KEY, false).commit();

                } else if (Sound == 0) {
                    Mute.setBackgroundResource(R.drawable.sound_high);
                    Sound = 1;
                    prefs.edit().putBoolean(MUTE_PRESSED_KEY, true).commit();
                }

            }

        });

    }

}