Saving belongsTo models Cakephp

I have the following m开发者_如何转开发odel associations:

Question belongsTo Category
Category hasMany Question
Question hasMany Answer
Answer belongsTo Question

I want to be able to create a new category when creating a Question, but I am getting a Category.id validation error, even though I am not sending setting the Category.id in the $this->data array. I successfully create new answers in the same form, but the Category is not being created.

My form:

<h3>Create multiple choice question</h3>
<?php

echo $this->Form->create('Question', array('action' => 'addmc'));
echo $this->Form->input('Question.name');
echo $this->Form->input('Question.questiontext', array('label' => 'Question Text (What students will see)'));
echo $this->Form->input('Question.generalfeedback', array('label' => 'General feedback (Feedback student will see when reviewing question)'));

for ($i = 0; $i < 4; $i++) {
    echo $this->Form->input('Answer.'.$i.'.answer', array('label' => 'Answer ' . ($i+1)));
    echo $this->Form->input('Answer.'.$i.'.score', array('label' => 'Score (Number from 0 to 100)'));
}
echo $this->Form->input('Category.0.name', array('label' => 'Category'));
echo $this->Form->button('Save question', array('class' => 'form'));
echo $this->Form->end();

?>

I am using saveAll in the controller. I tried by removing the validation rule for the Category.id. The save operation went through but the category was not created.

in the controller, you need to save the category first, get that inserted id and assign to category_id in the question, then you can use saveAll on the question and answers.

If Question belongsTo Category, you probably have a Question.category_id field... That one should be used for chosing the category in a select box (at least, that's how I think you want it to work). The way you are trying to achieve this now doesn't make sense to Cake.