TalkBackPreferencesActivity.java 文件源码

private void updateTalkBackShortcutStatus() {
    final TwoStatePreference preference = (TwoStatePreference) findPreferenceByResId(
            R.string.pref_two_volume_long_press_key);
    if (preference == null) {
        return;
    }
    if (Build.VERSION.SDK_INT >= ProcessorVolumeStream.MIN_API_LEVEL) {
        preference.setEnabled(
                TalkBackService.getInstance() != null || preference.isChecked());
    } else {
        final PreferenceGroup category = (PreferenceGroup) findPreferenceByResId(
                R.string.pref_category_miscellaneous_key);
        if (category == null) {
            return;
        }
        category.removePreference(preference);
    }

}