TalkBackPreferencesActivity.java 文件源码

/**
 * Ensure that the vibration setting does not appear on devices without a
 * vibrator.
 */
private void checkVibrationSupport() {
    Activity activity = getActivity();
    if (activity == null) {
        return;
    }

    final Vibrator vibrator = (Vibrator) activity.getSystemService(VIBRATOR_SERVICE);

    if (vibrator != null && vibrator.hasVibrator()) {
        return;
    }

    final PreferenceGroup category =
            (PreferenceGroup) findPreferenceByResId(R.string.pref_category_feedback_key);
    final TwoStatePreference prefVibration =
            (TwoStatePreference) findPreferenceByResId(R.string.pref_vibration_key);

    if (prefVibration != null) {
        prefVibration.setChecked(false);
        category.removePreference(prefVibration);
    }
}