SettingsActivity.java

package hk.hku.cs.srli.supermonkey;

import android.app.Activity;
import android.content.SharedPreferences;
import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
import android.os.Bundle;
import android.preference.EditTextPreference;
import android.preference.ListPreference;
import android.preference.Preference;
import android.preference.PreferenceFragment;
import android.preference.PreferenceGroup;
import android.preference.PreferenceScreen;
import android.support.v4.app.NavUtils;
import android.view.MenuItem;

public class SettingsActivity extends Activity {

    public static final String KEY_PREF_M_PORT = "pref_m_port";
    public static final String KEY_PREF_ET_HOST = "pref_et_host";
    public static final String KEY_PREF_ET_PORT = "pref_et_port";
    public static final String KEY_PREF_ET_AUTOCONNECT = "pref_et_autoconnect";
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // Display the fragment as the main content.
        getFragmentManager().beginTransaction()
                .replace(android.R.id.content, new SettingsFragment())
                .commit();
        getActionBar().setDisplayHomeAsUpEnabled(true);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                NavUtils.navigateUpFromSameTask(this);
                return true;
        }
        return super.onOptionsItemSelected(item);
    }

    public static class SettingsFragment extends PreferenceFragment implements
            OnSharedPreferenceChangeListener {

        private PreferenceScreen ps;

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);

            // Load the preferences from an XML resource
            addPreferencesFromResource(R.xml.preferences);

            ps = getPreferenceScreen();

            initSummaries(ps);
        }

        @Override
        public void onResume() {
            super.onResume();

            // Set up a listener whenever a key changes
            ps.getSharedPreferences().registerOnSharedPreferenceChangeListener(this);
        }

        @Override
        public void onPause() {
            super.onPause();

            // Unregister the listener whenever a key changes
            ps.getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this);
        }

        @Override
        public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
            updateSummary(findPreference(key));
        }

        private void initSummaries(PreferenceGroup pg) {
            for (int i = 0; i < pg.getPreferenceCount(); i++) {
                Preference p = pg.getPreference(i);
                if (p instanceof PreferenceGroup) {
                    initSummaries((PreferenceGroup) p);
                } else updateSummary(p);
            }
        }

        private void updateSummary(Preference p) {
            if (p instanceof ListPreference) {
                ListPreference listPref = (ListPreference) p;
                p.setSummary(listPref.getEntry());
            }
            if (p instanceof EditTextPreference) {
                EditTextPreference editTextPref = (EditTextPreference) p;
                p.setSummary(editTextPref.getText());
            }
        }
    }

}