Reorder menu items without affecting database id - laravel

Question

I have a menu in my Laravel application which lists tags. I want to be able to add more tags and change their order, but I don't want to affect the underlying database ids for each tag. Because that would break any data I have already associated with them. So I thought I add an extra column to my database called 'display_order' like so:
Database:
Schema::create('tags', function (Blueprint $table) {
$table->increments('id');
$table->integer('display_order');
$table->string('name');
$table->timestamps();
});
Now I want to create a view to let the user change the value of the display_order field. Initially I show a page which prints each tag and its display_order and allows the user to update the value in a text field:
Controller:
public function showTagsOrder()
{
$tags = Tag::all()->sortBy('display_order');
return view('menu.tags', compact('tags'));
}
Route:
Route::get('/menu/tags', ['as' => 'menu_tags', 'uses' => 'MenuOrderController#showTagsOrder']);
View:
{!! Form::open(['action' => 'MenuOrderController#updateTagsOrder']) !!}
#foreach($tags->chunk(18) as $chunk)
<div class="col">
#foreach($chunk as $tag)
<p><label>{!! $tag->name !!}</label><input type="text" name="tag_array[{!! $tag->id !!}]" value="{!! $tag->display_order !!}" class="numeric" />
#endforeach
</div>
#endforeach
<p>{!! Form::submit('Submit') !!}
{!! Form::close() !!}
When the form is submitted I then have the following function in my controller:
public function updateTagsOrder(TagsMenuRequest $request)
{
$i = 1;
foreach($request->tag_array as $tag_value)
{
$tag = new Tag;
$tag = Tag::find($i);
$tag->display_order = $tag_value;
$tag->save();
$i++;
}
flash()->overlay('The order of tags in the menu has been udpated!', 'Congratulations');
return redirect('/');
}
But this doesn't work. How would I rewrite this so I assigned the correct value for display_order to each tag. I'd be very grateful for your help.

Answer 1

foreach($request->tag_array as $tag_id => $tag_value)
{
$tag = Tag::find($tag_id);
$tag->display_order = $tag_value;
$tag->save();
}