FormHelper individual checkbox for hasMany relation

Question

I'm currently building a form where Permissions are assigned to Roles through a Belongs-To-Many relationship. This is currently on my Add Role view. I managed to get multiple checkboxes and the association working by using:

echo $this->Form->input('Roles.permissions._ids', [
    'label' => false,
    'type' => 'select',
    'multiple' => 'checkbox',
    'options' => $permissions
]);

That worked, but the list of Permissions is growing and needs some sort of organization. So now I have used map/reduce to group these permissions by a Category field, and that works to pass into the view. N

My problem exists when I try to manually loop through each Permission result and assign the entity ID and label to different checkbox inputs throughout the View, but in the same array.

Here is the closest I can get it to actually putting the values in the correct format for the _ids array to save the belongsToMany association:

echo $this->Form->input('Roles.permissions._ids[]', [
    'id' => 'roles-permissions-ids-' . $permission->PermissionId,
    'type' => 'checkbox',
    'label' => $permission->DisplayName,
    'value' => $permission->PermissionId,
    'hiddenField' => false
]);

This allows the selections to end up in the correct array and make it into the merged entity, but it throws the following warning:

Notice (8): Array to string conversion [CORE\src\View\Widget\CheckboxWidget.php, line 80]

The data entered in the form does not make it back into the form inputs, but appears to be correct everywhere else. I've tried manually adding the hidden input, tweaking the input IDs, and just about anything else. This is the best way I could get the data to post right.

After looking at the CakePHP source code (on version 3.1.11) at the CheckboxWidget, I noticed the isChecked function returns return (string)$data['val'] === (string)$data['value']; but somehow it is getting the entire array.

I modified just before the return statement and it technically works, but obviously isn't the right, long-term solution:

if (is_array($data['val'])) {
    // value was right, so just copy it over to val
    $data['val'] = $data['value'];
}

If anyone knows if I'm doing something wrong or if this is a bug in the framework, it would help me out a lot.

Answer 1

Your input method call needs to look like

echo $this->Form->input('permissions._ids', [
    'label' => false,
    'type' => 'select',
    'multiple' => 'checkbox',
    'options' => $permissions,
    'hiddenField' => false
]);

The Roles need to be removed.