java - Firebase 身份验证 : with Sign in existing user

Question

当使用相同的电子邮件地址和密码登录现有用户时，响应始终为“无法登录，请检查您的电子邮件和密码，然后重试”

private void loginUser(String email, String password) {

    mAuth.signInWithEmailAndPassword(email, password).addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
        @Override
        public void onComplete(@NonNull Task<AuthResult> task) {

            if (!task.isSuccessful()){ 

               mLoginProgress.dismiss();  

                Intent mainIntent = new Intent(LoginActivity.this, MainActivity.class);
                startActivity(mainIntent);
                finish();
            }
            else {
                mLoginProgress.hide();

                Toast.makeText(LoginActivity.this,
                        "Cannot sign in. Please check your email and password and try again.", Toast.LENGTH_SHORT).show();
            }

        }
    });
}

Answer 1

当响应成功时，您可以使用 ! 将其变为失败

(!task.isSuccessful()) => (!true)
=> (false)

因此删除否定运算符 (!)

if (task.isSuccessful())

代码

mAuth.signInWithEmailAndPassword(email, password).addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
        @Override
        public void onComplete(@NonNull Task<AuthResult> task) {

            if (task.isSuccessful()){ // success
                //..code
            }
            else {  // failure
                //..code
            }
        }
    });
}