CakePHP: Get category ID from Categories table and insert to a column in Items table

I'm new to CakePHP and I trying out some of the tutorials on it.

Currently I have a Categories table and an Items table; Category hasMany Item and Item belongsTo a Category.

On my Items table, I have a category_id column that refers to a category ID in the Categories table.

A user is only limited to adding an item t开发者_如何学Pythonhrough the categories view.ctp page and it'll redirect user to the items add.ctp page. The add() function resides in the items controller.

How do I get the ID of the category which the user wish to add an item to and insert them to category_id column whenever a user adds an item?

Thanks in advance.

In the controller:

public function add() {
    if ($this->data) {
        if ($this->Item->save($this->data)) {
            $this->redirect(…);
        }
    }

    $categories = $this->Item->Category->find('list');
    $this->set(compact('categories'));
}

The view:

echo $this->Form->input('category_id');

(which is equivalent to:)

echo $this->Form->input('category_id', array('type' => 'select', 'options' => $categories));

You just need to get a list of categories, which find('list') is specialized for, and an input element which lets the user select a category. The category_id will be saved like any other field of the Item model.

If you want to prefill the category from a different page, use something like this:

public function add($category_id) {
    $category = $this->Item->Category->find('first', array('conditions' => array('Category.id' => $category_id), 'recursive' => -1));
    if (!$category) {
        $this->Session->setFlash('Select a valid category');
        $this->redirect(array('controller' => 'categories', 'action' => 'select_category'));
    }

    if ($this->data) {
        $this->data['Item']['category_id'] = $category_id;
        if ($this->Item->save($this->data)) {
            $this->redirect(…);
        }
    }

    $this->set(compact('category'));
}

View:

<p>Adding item to category <?php echo $category['Category']['name']; ?></p>
<?php echo $this->Form->create('Item', array('url' => array('action' => 'add', $category['Category']['id']))); ?>

From your category selection list, just link to the Item add action:

echo $this->Html->link("Add item to {$category['Category']['name']}", array('controller' => 'item', 'action' => 'add', $category['Category']['id']));