使用Leancloud短信sdk获取验证码出现 java.lang.StringIndexOutOfBoundsException: length=0; index=8,造成闪退

获取验证码

 private void getSms() {
        phone = phoneRegisterEt.getText().toString().trim();
        AVSMSOption avsmsOption = new AVSMSOption();
        avsmsOption.setTtl(10);
        avsmsOption.setTemplateName("旅伴注册");
        avsmsOption.setSignatureName("旅伴App");
        AVSMS.requestSMSCodeInBackground(phone, avsmsOption).subscribe(new Observer<AVNull>() {
            @Override
            public void onSubscribe(Disposable d) {
            }

            @Override
            public void onNext(AVNull avNull) {
                Log.d("TAG", "Result: Successfully sent verification code.");
                Toast.makeText(RegisterActivity.this, "验证码已发送", Toast.LENGTH_LONG).show();
            }

            @Override
            public void onError(Throwable e) {
                Log.d("TAG", "Result: Failed to send verification code. Reason: " + e.getMessage());
                Toast.makeText(RegisterActivity.this, "验证码发送失败", Toast.LENGTH_LONG).show();
            }

            @Override
            public void onComplete() {

            }
        });
    }

验证

 private void verifySmsCode() {
        smscode = smsRegisterEt.getText().toString();
        phone = phoneRegisterEt.getText().toString().trim();
        AVSMS.verifySMSCodeInBackground(smscode, phone).subscribe(new Observer<AVNull>() {
            @Override
            public void onSubscribe(Disposable d) {

            }

            @Override
            public void onNext(AVNull avNull) {
                Log.d("TAG", "Result: Successfully verified the number.");
                register();
            }

            @Override
            public void onError(Throwable e) {
                Log.d("TAG", "Result: Failed to verify the number. Reason: " + e.getMessage());
                checkSmscode(smscode);
            }

            @Override
            public void onComplete() {

            }
        });
    }

哪一行呢?