Undefined variable in laravel blade partial view error - php

Question

I am getting the following error when loading a page:
Undefined variable: userIds
However, the variavle is reaching the partial given when I try {{ isset($userIds) ? 'Yes' : 'No' }} it returns 'Yes' when the block of code is reached.
The error occurs with the variable $userIds in the following input type:
</li>
#foreach ($users as $index => $user)
<li class="list-group-item"
style="{{ (isset($usersFiltered) && is_array($usersFiltered) && !in_array($user->id, $usersFiltered) ) ?
'display: none;' : ''}}">
<div class="checkbox">
<label>
<input type="checkbox" class="awe-selectable" id="users[{{ $index }}]" name="users[{{ $index }}]"
value="{{ $user->id }}" {{ in_array($user->id,$userIds) ? 'checked' : '' }}>
<label for="users[{{ $index }}]">{{ $user->name }}</label>
</label>
</div>
</li>
#endforeach
My controller code sending the variable to the partial:
return view('core::admin.groups.partials._users_form', [
'group' => $group,
'users' => $users,
'usersFiltered' => $usersFiltered,
'userIds' => $userIds,
]);
Is it a syntax mistake? If I replace $userIds by any of the other variables, those too will return the same "undefined" error (f.e. with $usersFiltered)
Thanks in advance, will edit the post with more information as needed.

Answer 1

Solved!
The issue was that when the page was rendered, the variable was not defined in the main page render (/create), only in the method that rendered the partial, so when I was opening the main window, the variable was not yet defined because it was only received from the controller once a filter was applied.
Sollution:
/**
* GET: /admin/security/groups/create
*/
public function create()
{
**$userIds = !empty($request['userIds']) ? $request['userIds'] : [];**
(...)
return view('core::admin.groups.create', [
'group' => new Group,
**'userIds' => $userIds,**
'users' => $users,
'isCreating' => true,
]);

Answer 2

the syntax looks good to me, but I would suggest to you to do this:
// in your controller
foreach ($users as $user) {
$user->checked = false;
if ((is_array($userIds) and !empty($userIds)) and in_array($user->id, $userIds)) {
$user->checked = true;
}
}
now there is no need to send the $userIds to the view, since you fixed it in the controller.
// in your view
<input type="checkbox" class="awe-selectable" id="users[{{ $index }}]" name="users[{{ $index }}]" value="{{ $user->id }}" {{ ($user->checked) ? 'checked' : '' }}>
Happy coding!