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A PHP Error was encountered
Severity: Notice
Message: Undefined property: Home::$page_model
Filename: controllers/home.php
Line Number: 14
Backtrace:
File: C:\xampp\htdocs\ci3\application\controllers\home.php
Line: 14
Function: _error_handler
File: C:\xampp\htdocs\ci3\index.php
Line: 292
Function: require_once


An uncaught Exception was encountered
Type: Error
Message: Call to a member function find_ID() on null
Filename: C:\xampp\htdocs\ci3\application\controllers\home.php
Line Number: 14
Backtrace:
File: C:\xampp\htdocs\ci3\index.php
Line: 292
Function: require_once


How to fix those error?

home.php

PHP Code:

$this->data['page_detail'] = $this->page_model->find_ID(); 


ci3/index.php

PHP Code:

require_once BASEPATH.'core/CodeIgniter.php'; 


Why the error appears?

models/page_model.php

PHP Code:

public function find_ID($post_ID = false)
    {
        $this->db->select('post.*, template.*');
        $this->db->from('post');
        $this->db->join('template', 'template.template_ID = post.post_template_ID', 'left');
        if ($post_ID)
            $this->db->where(array('post.post_type' => 'page', 'post.post_ID' => $post_ID, 'post.post_status' => 1));
        else
        {
            $this->db->where(array('post.post_type' => 'page', 'post.post_status' => 1));
            $this->db->order_by('post.post_position');
        }
        $this->db->limit(1);
        $q = $this->db->get();
        
        if($q->num_rows() > 0)
            return $q->row();
        
        return false;
    } 


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