如何解决这个空的OTP编辑文字错误？

Question

当我尝试验证一个空的editText（OTP）时，我“不幸的是应用程序已停止”，我想要做的就是试图在用户尝试验证一个空的editText（OTP）时举杯。

我试图在if语句中禁用按钮（如果mcodeText为空，则禁用按钮），但是，因为im使用带有按钮整数的单个按钮来获取OTP并验证它是否无效

public class LoginActivity extends AppCompatActivity {

 private LinearLayout mLayout, nLayout;
 private EditText mPhoneText, mCodeText;
 private TextView mTextview, nTextview, kTexiview;
 private Button mButton, mButton2;
 private FirebaseAuth mAuth;
 private String mVerificationId;
 private PhoneAuthProvider.ForceResendingToken mResendToken;
 private int btnType = 0;
 private PhoneAuthProvider.OnVerificationStateChangedCallbacks mCallbacks;
 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_login);
  mAuth = FirebaseAuth.getInstance();
  mLayout = (LinearLayout) findViewById(R.id.PhoneOL);
  nLayout = (LinearLayout) findViewById(R.id.socialL);
  mTextview = (TextView) findViewById(R.id.textView17);
  kTexiview = (TextView) findViewById(R.id.textView21);
  kTexiview.setVisibility(View.GONE);
  nTextview = (TextView) findViewById(R.id.TandC);
  mCodeText = (EditText) findViewById(R.id.editText2);
  mButton = (Button) findViewById(R.id.buttonP);
  mPhoneText = (EditText) findViewById(R.id.editText);
  mPhoneText.setText("+91-");
  Selection.setSelection(mPhoneText.getText(), mPhoneText.getText().length());
  mPhoneText.addTextChangedListener(new TextWatcher() {

   @Override
   public void onTextChanged(CharSequence s, int start, int before, int count) {
    // TODO Auto-generated method stub
   }

   @Override
   public void beforeTextChanged(CharSequence s, int start, int count,
    int after) {
    // TODO Auto-generated method stub
   }

   @Override
   public void afterTextChanged(Editable s) {
    if (!s.toString().startsWith("+91-")) {
     mPhoneText.setText("+91-");
     Selection.setSelection(mPhoneText.getText(), mPhoneText.getText().length());
    }
   }
  });

  mButton2 = (Button) findViewById(R.id.phone1);
  mButton2.setOnClickListener(new View.OnClickListener() {

   @Override
   public void onClick(View view) {
    mButton2.setVisibility(View.GONE);
    mLayout.setVisibility(View.VISIBLE);
    mTextview.setVisibility(View.GONE);
    nLayout.setVisibility(View.GONE);
    nTextview.setVisibility(View.GONE);
    kTexiview.setVisibility(View.VISIBLE);
    mCodeText.setVisibility(View.GONE);
   }
  });
  mButton = (Button) findViewById(R.id.buttonP);
  mButton.setOnClickListener(new View.OnClickListener() {
   @Override
   public void onClick(View view) {

    if (btnType == 0) {
     String phoneNumber = mPhoneText.getText().toString();
     PhoneAuthProvider.getInstance().verifyPhoneNumber(
      phoneNumber, 60, TimeUnit.SECONDS,
      LoginActivity.this, mCallbacks);

     mCodeText.setVisibility(View.VISIBLE);
     mPhoneText.setVisibility(View.GONE);
     mButton.setText("Sing In");
    } else {
     String verificationCode = mCodeText.getText().toString();
     PhoneAuthCredential credential = PhoneAuthProvider.getCredential(mVerificationId, verificationCode);
     signInWithPhoneAuthCredential(credential);
    }
   }
  });

  mCallbacks = new PhoneAuthProvider.OnVerificationStateChangedCallbacks() {
   @Override
   public void onVerificationCompleted(PhoneAuthCredential phoneAuthCredential) {
    signInWithPhoneAuthCredential(phoneAuthCredential);
   }

   @Override
   public void onVerificationFailed(FirebaseException e) {

    Toast.makeText(getApplicationContext(),
     "Enter a Valid Number", Toast.LENGTH_SHORT).show();
    mPhoneText.setVisibility(View.VISIBLE);
    mPhoneText.setText("");
    mCodeText.setVisibility(View.GONE);
    mButton.setText("Proceed");
   }

   @Override
   public void onCodeSent(String verificationId,
    PhoneAuthProvider.ForceResendingToken token) {

    mVerificationId = verificationId;
    mResendToken = token;
    btnType = 1;
   }
  };
 }

 private void signInWithPhoneAuthCredential(PhoneAuthCredential credential) {
  mAuth.signInWithCredential(credential)
   .addOnCompleteListener(this, new OnCompleteListener < AuthResult > () {
    @Override
    public void onComplete(@NonNull Task < AuthResult > task) {
     if (task.isSuccessful()) {
      // Sign in success, update UI with the signed-in user's information

      FirebaseUser user = task.getResult().getUser();

      Intent intent = new Intent(LoginActivity.this,
       MainActivity.class);
      startActivity(intent);
      finish();

      Toast.makeText(getApplicationContext(),
       "Logged in Successfully", Toast.LENGTH_SHORT).show();
     } else {
      // Sign in failed, display a message and update the UI
      Toast.makeText(getApplicationContext(),
       "Your entered wrong OTP, Try again",
       Toast.LENGTH_SHORT).show();
     }
    }
   });
 }
}