GroceryCrud parent category

gcud-parent.php

<?php
function _navigation()
	{

		$this->crud->set_crud_url_path(site_url('admin/index/index/navigation'));

		$this->crud->set_table('navigation');

		$this->crud->columns('name', 'parent_id');

		$this->crud->unset_delete();
		$this->crud->unset_add();

		$this->crud->fields('name', 'parent_id');

		/* Add this customisation for parent_relation */
		$primary_id_field    = 'id';
		$table_name          = 'navigation';
		$relation_field_name = 'parent_id';
		$parent_field        = 'parent_id';
		$title_field         = 'name_pl';
		$title_display_as    = 'Chose parent category';

		$same_table = TRUE; //not required, the default is false

		$this->set_parent_relation($primary_id_field, $table_name, $parent_field, $title_field, $this->crud, $title_display_as, $relation_field_name, NULL, $same_table);

		$this->data['crud'] = $this->crud->render();
	}


	/**
	 * @param      $primary_id_field
	 * @param      $table_name
	 * @param      $parent_field
	 * @param      $title_field
	 * @param      $crud
	 * @param      $title_display_as
	 * @param      $relation_field_name
	 * @param null $where
	 * @param bool $same_table
	 */
	function set_parent_relation($primary_id_field, $table_name, $parent_field, $title_field, $crud, $title_display_as, $relation_field_name, $where = NULL, $same_table = FALSE)
	{
		$this->gc_id               = $primary_id_field;
		$this->gc_table            = $table_name;
		$this->gc_field_name       = $relation_field_name;
		$this->gc_parent           = $parent_field;
		$this->gc_title            = $title_field;
		$this->gc_where            = $where;
		$this->gc_title_display_as = $title_display_as;
		$this->gc_same_table       = $same_table;

		$crud->set_css('assets/grocery_crud/css/jquery_plugins/chosen/chosen.css');
		$crud->set_js('assets/grocery_crud/js/jquery-1.10.2.min.js');
		$crud->set_js('assets/grocery_crud/js/jquery_plugins/jquery.chosen.min.js');
		$crud->set_js('assets/grocery_crud/js/jquery_plugins/ajax-chosen.js');
		$crud->set_js('assets/grocery_crud/js/jquery_plugins/config/jquery.chosen.config.js');

		$crud->set_relation($this->gc_field_name, $this->gc_table, $this->gc_title);

		$crud->callback_field($this->gc_field_name, array($this, 'parent_relation_callback'));
	}

	/**
	 * @param string $value
	 * @param null   $primary
	 *
	 * @return string
	 */
	function parent_relation_callback($value = '', $primary = NULL)
	{
		if (! empty($value))
		{
			$this->gc_history = $this->get_parent_history($value);
		}

		$return_string = '<script type="text/javascript"> var ajax_relation_url = ""; </script>';
		$return_string .= '<select name="' . $this->gc_field_name . '" class="chosen-select" data-placeholder="' . $this->gc_title_display_as . '"><option value=""></option>';
		$return_string .= $this->parent_repeat(NULL, - 1, $value);
		$return_string .= '</select>';

		return $return_string;
	}

	/**
	 * @param null   $parent
	 * @param        $tree_level
	 * @param string $value
	 *
	 * @return string
	 */
	function parent_repeat($parent = NULL, $tree_level = -1, $value = '')
	{
		$return_string = '';

		if ($this->gc_where !== NULL)
		{
			$this->db->where($this->gc_where);
		}
		if ($parent === NULL)
		{
			$this->db->where($this->gc_parent . ' IS NULL');
		}
		else
		{
			$this->db->where($this->gc_parent, $parent);
		}
		$db_result = $this->db->get($this->gc_table);

		if ($db_result->num_rows() > 0)
		{
			$tree_level ++;
			foreach ($db_result->result() as $result)
			{
				$tree_string = $tree_level != 0 ? '|' . str_repeat('-', $tree_level * 4) : '';
				$selected    = $value !== '' && $value == $result->{$this->gc_id} ? 'selected = "selected"' : '';
				$disabled    = $this->gc_same_table && ! empty($value) && in_array($result->{$this->gc_id}, $this->gc_history) ? 'disabled="disabled"' : '';

				$return_string .= "<option value='" . $result->{$this->gc_id} . "' {$selected} {$disabled} >{$tree_string} " . $result->{$this->gc_title} . "</option>";
				$return_string .= $this->parent_repeat($result->{$this->gc_id}, $tree_level, $value);
			}
		}

		return $return_string;
	}

	/**
	 * @param $id
	 *
	 * @return array
	 */
	function get_parent_history($id)
	{
		$history = array();

		$this->db->where($this->gc_id, $id);
		$result = $this->db->get($this->gc_table)->row();

		$history[] = $result->{$this->gc_id};

		while (! empty($result->{$this->gc_parent}))
		{
			$this->db->where($this->gc_id, $result->{$this->gc_parent});
			$result = $this->db->get($this->gc_table)->row();

			$history[] = $result->{$this->gc_id};
		}

		return $history;
	}