How to add Pagination in custom plugin list page

Question

I have created a plugin for data insert from WP dashboard. Data has inserted & updated successfully, I want to add a pagination on my list(view)page. I am new developer. this my list-page code.

<?php
function wp_schools_list() {
    ?>
    <link type="text/css" href="<?php echo WP_PLUGIN_URL; ?>mywp/sinetiks-schools/style-admin.css" rel="stylesheet" />

    <div class="wrap abs">
        <h2>Schools</h2>
        <div class="tablenav top">
            <div class="alignleft actions">
                <a href="<?php echo admin_url('admin.php?page=mywp_schools_create'); ?>">Add New</a>
            </div>
            <br class="clear">
        </div>
        <?php
        $path_array = wp_upload_dir()['baseurl']; // wp_upload_dir has diffrent types of array I am used 'baseurl' for path
        global $wpdb;
        $table_name = $wpdb->prefix . "school";

        $rows = $wpdb->get_results("SELECT id,code,name,image_name from $table_name");
        ?>
        <table class='wp-list-table widefat fixed striped posts'>
            <tr>
                <th class="manage-column ss-list-width">ID</th>
                <th class="manage-column ss-list-width">Code</th>
                <th class="manage-column ss-list-width">Name</th>
                <th class="manage-column ss-list-width">Image</th>
                <th>&nbsp;</th>
                <th>&nbsp;</th>
            </tr>
            <?php foreach ($rows as $row) { ?>
                <tr>
                    <td class="manage-column ss-list-width"><?php echo $row->id; ?></td>
                    <td class="manage-column ss-list-width"><?php echo $row->code; ?></td>
                    <td class="manage-column ss-list-width"><?php echo $row->name; ?></td>

                    <td><img src="<?php echo $path_array; ?>/2016/12/<?php echo  $row->image_name;?> " width="100" height="100" /> </td>
                    <td><a href="<?php echo admin_url('admin.php?page=wp_schools_update&id=' . $row->id); ?>">Update</a></td>
                    <td><a href="<?php echo admin_url('admin.php?page=wp_schools_delete&id=' . $row->id); ?>">Delete</a></td>


                </tr>
            <?php }  ?>
        </table>
    </div>
    <?php

}

Answer 1

Try this code.

<?php

    function wp_schools_list() {
        global $wpdb;
        $table_name = $wpdb->prefix . "school";

        $pagenum = isset( $_GET['pagenum'] ) ? absint( $_GET['pagenum'] ) : 1;      

        $limit = 10; // number of rows in page
        $offset = ( $pagenum - 1 ) * $limit;
        $total = $wpdb->get_var( "select count(*) as total from $table_name" );
        $num_of_pages = ceil( $total / $limit );

        $rows = $wpdb->get_results( "SELECT id,code,name,image_name from $table_name limit  $offset, $limit" );
        $rowcount = $wpdb->num_rows;

    ?>
        <link type="text/css" href="<?php echo WP_PLUGIN_URL; ?>mywp/sinetiks-schools/style-admin.css" rel="stylesheet" />

        <div class="wrap abs">
            <h2>Schools</h2>
            <div class="tablenav top">
                <div class="alignleft actions">
                    <a href="<?php echo admin_url('admin.php?page=mywp_schools_create'); ?>">Add New</a>
                </div>
                <br class="clear">
            </div>
            <?php
            $path_array = wp_upload_dir()['baseurl']; // wp_upload_dir has diffrent types of array I am used 'baseurl' for path

            ?>
            <table class='wp-list-table widefat fixed striped posts'>
                <tr>
                    <th class="manage-column ss-list-width">ID</th>
                    <th class="manage-column ss-list-width">Code</th>
                    <th class="manage-column ss-list-width">Name</th>
                    <th class="manage-column ss-list-width">Image</th>
                    <th>&nbsp;</th>
                    <th>&nbsp;</th>
                </tr>
                <?php
                if($rowcount>0){
                foreach ($rows as $row) { ?>
                    <tr>
                        <td class="manage-column ss-list-width"><?php echo $row->id; ?></td>
                        <td class="manage-column ss-list-width"><?php echo $row->code; ?></td>
                        <td class="manage-column ss-list-width"><?php echo $row->name; ?></td>

                        <td><img src="<?php echo $path_array; ?>/2016/12/<?php echo  $row->image_name;?> " width="100" height="100" /> </td>
                        <td><a href="<?php echo admin_url('admin.php?page=wp_schools_update&id=' . $row->id); ?>">Update</a></td>
                        <td><a href="<?php echo admin_url('admin.php?page=wp_schools_delete&id=' . $row->id); ?>">Delete</a></td>


                    </tr>
                <?php } }else{
                    echo "<tr><td cols=an='5'>No records found</td></tr>";
                } ?>
            </table>
        </div>
        <?php

        $page_links = paginate_links( array(
            'base' => add_query_arg( 'pagenum', '%#%' ),
            'format' => '',
            'prev_text' => __( '&laquo;', 'text-domain' ),
            'next_text' => __( '&raquo;', 'text-domain' ),
            'total' => $num_of_pages,
            'current' => $pagenum
        ) );

        if ( $page_links ) {
            echo '<div class="tablenav" style="width: 99%;"><div class="tablenav-pages" style="margin: 1em 0">' . $page_links . '</div></div>';
        }
}

Updated