SettingsFragment.java 文件源码

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

    SharedPreferences sharedPreferences = getPreferenceScreen().getSharedPreferences();

    // Register self als listener for changes
    sharedPreferences.registerOnSharedPreferenceChangeListener(this);

    // Set initial summary state
    for (int i = 0; i < getPreferenceScreen().getPreferenceCount(); i++) {
        Preference preference = getPreferenceScreen().getPreference(i);

        if (preference instanceof PreferenceGroup) {
            PreferenceGroup preferenceGroup = (PreferenceGroup) preference;
            for (int j = 0; j < preferenceGroup.getPreferenceCount(); j++) {
                updatePreferenceSummary(sharedPreferences, preferenceGroup.getPreference(j));
            }
        } else {
            updatePreferenceSummary(sharedPreferences, preference);
        }
    }
}