title: OnPreferenceChangeListener for every setting
body: <p>I know that I can do something like this:</p>
  
  <pre><code>Preference pref = findPreference(getString(R.string.pref_vibrate_on_key));
  pref.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {
  
          @Override
          public boolean onPreferenceChange(Preference preference,
                  Object newValue) {
              LogUtil.d("Working!");
              return true;
          }
  
  });
  </code></pre>
  
  <p>But I would like to add a Listener to every preference.
  I tried doing:</p>
  
  <pre><code>SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(context);
  sp.registerOnSharedPreferenceChangeListener(new OnSharedPreferenceChangeListener() {
  
          @Override
          public void onSharedPreferenceChanged(
                  SharedPreferences sharedPreferences, String key) {
              LogUtil.d("working!");
  
          }
  
  });
  </code></pre>
  
  <p>but it doesn't work.
  Is this possible? If so, what am I doing wrong?</p>