Codeigniter - banner page choose file php errors

I am new in CodeIgniter, I'm making an admin panel for all static pages, option is user click on choose file and select a file click to update banner and its uploaded and display on page but when i directly click on Update Banner button so it shows an php error, now i want to know two things first how I will rectify this error secondly is there any alert thing here so i mention the user to first upload file then click omegle.2yu.co update banner button, please suggest omeglz echat i already provide php errors & coding of banner page.

A PHP Error was encountered
Severity: Notice
Message: Undefined variable: banner
Filename: backend/inside_banner.php
Line Number: 2

A PHP Error was encountered
Severity: Notice
Message: Undefined variable: page_id
Filename: backend/inside_banner.php
Line Number: 9

Code

class Banner extends My_Controller {

    function __construct() {
        parent::__construct();
    }

    public function index() {
        if ($this->input->post('submit')) {
            $upload_data = upload_file('banners', array('jpg|png|jpeg|gif'), '2028');
            if ($upload_data['error_flag']) {
                $this->data['errors']['banner'] = $upload_data['errors'];
                $this->data['data'] = $_POST;
                $this->template->write_view('content', 'backend/banner_view', $this->data);
                $this->template->render();
            } else {
                $posted_data = $_POST;
                $posted_data['file_name'] = $upload_data['upload_data']['file_name'];
                $posted_data['lang_id'] = $this->data['lang_id'];
                $b = new Banners();
                $b->addBanner($posted_data);
                redirect('admin/banner');
            }
        }

    $this->data['page_title'] = 'Add Banner';
    $this->template->add_css('layout/css/form.css');

    $this->data['allBanners'] = BannersTable::getAllBanners($this->data['lang_id']);

    $this->template->write_view('content', 'backend/banner_view', $this->data);
    $this->template->render();
}

public function delete($banner_id) {
    $b = new Banners();
    $b->deleteBanner($banner_id);

    redirect('admin/banner');
}

public function inside($page_id) {
    if ($this->input->post('submit')) {
        $upload_data = upload_file('inside_banners', array('jpg|png|jpeg|gif'), '2028');
        if ($upload_data['error_flag']) {
            $this->data['errors']['banner'] = $upload_data['errors'];
            $this->data['data'] = $_POST;
            $this->template->write_view('content', 'backend/inside_banner', $this->data);
            $this->template->render();
        } else {
            $posted_data = $_POST;
            $posted_data['page_id'] = $page_id;
            $posted_data['file_name'] = $upload_data['upload_data']['file_name'];
            $posted_data['lang_id'] = $this->data['lang_id'];
            $ib = new InsideBanners();
            $ib->addInsideBanner($posted_data);
            redirect('admin/banner/inside/' . $page_id);
        }
    }

    if ($page_id) {
        $this->data['page_title'] = 'Add ' . $page_id . ' Banner';
        $this->template->add_css('layout/css/form.css');

        $this->data['page_id'] = $page_id;
        $this->data['banner'] = InsideBannersTable::getOne($page_id);
        // var_dump($this->data['banner']);exit;

        $this->template->write_view('content', 'backend/inside_banner', $this->data);
        $this->template->render();
    } else {
        redirect('admin/dashboard');
    }
}

public function arrange(){
    $b = new Banners();
    $b->updateBannersOrder($_POST);

    redirect('admin/banner');
}

}

?>

Undefined variable: banner - Filename: backend/inside_banner.php
Undefined variable: page_id - Filename: backend/inside_banner.php

As you can see it's telling you right where the errors are.

In otherwords both variables are undefined, you need to define the variables.

What did you Try? What did you Get? What did you Expect?

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