private LockscreenCredential mChosenPassword;
    LockPatternUtils mLockPatternUtils;

   mLockPatternUtils = new LockPatternUtils(this);
   int userId = UserHandle.myUserId();

public void createPin(String password) {
        // final String passwordText = "123456";
        mChosenPassword = LockscreenCredential.createPin(password);
        //  mChosenPassword = LockscreenCredential.createNone();
        Log.i(TAG, "mChosenPassword =" + mChosenPassword);
        //设置PIN码
        final boolean success = mLockPatternUtils.setLockCredential(mChosenPassword, LockscreenCredential.createNone(), userId);
        Log.i(TAG, "success =" + success);
        //取消PIN码设置
        final boolean successclean = mLockPatternUtils.setLockCredential(LockscreenCredential.createNone(), mChosenPassword, userId);
        Log.i(TAG, "successclean =" + successclean);
    }