title: Add Button on Custom Plugin in WordPress
body: <p>I am working on custom plugin in WP.I have showed the data in table format.Now i am trying to add functionality to plugin.But my table missing header and footer just like normal data listing in WP like Pages and Posts etc.Also i added the new button link.Either this is the right way ? I want to load my page on button clickMy code is :</p>
  
  <p><img src="https://i.stack.imgur.com/PI2fZ.png" alt="enter image description here"></p>
  
  <pre><code>function extra_tablenav( $which ) {
     if ( $which == "top" ){
        //The code that goes before the table is here
        echo '&lt;h2&gt;Letter Templates &lt;a href="http://localhost/letter/wp-content/plugins/letter/add-letter.php?type=new" class="add-new-h2"&gt;Add New&lt;/a&gt;&lt;/h2&gt;';
     }
  
  }
  
  function get_columns() {
     return $columns= array(
        'col_id'=&gt;__('ID'),
        'col_name'=&gt;__('Name'),
        'col_url'=&gt;__('Url'),
        'col_description'=&gt;__('Description')
     );
  }
  public function get_sortable_columns() {
     return $sortable = array(
        'col_id'=&gt;'id',
        'col_name'=&gt;'name'
     );
  }
  </code></pre>