Hi, I am trying to create custom formats for the Format dropdown, but the example on the WordPress and other sites, does not work. Do you have a specific method for adding or modifying the dropdown for custom styles?

From my functions.php in the gillion-child theme.

// Callback function to insert 'styleselect' into the $buttons array// Callback function to insert 'styleselect' into the $buttons arrayfunction my_mce_buttons_2( $buttons ) { array_unshift( $buttons, 'styleselect' ); return $buttons;}// Register our callback to the appropriate filteradd_filter( 'mce_buttons_2', 'my_mce_buttons_2' );
add_filter( 'tiny_mce_before_init', 'fb_mce_before_init' );
function fb_mce_before_init( $settings ) {
    $style_formats = array(        array(            'title' => 'Download Link',            'selector' => 'a',            'classes' => 'download'            ),        array(            'title' => 'My Test',            'selector' => 'p',            'classes' => 'mytest',        ),        array(            'title' => 'AlertBox',            'block' => 'div',            'classes' => 'alert_box',            'wrapper' => true        ),        array(            'title' => 'Red Uppercase Text',            'inline' => 'span',            'styles' => array(                'color'         => 'red', // or hex value #ff0000                'fontWeight'    => 'bold',                'textTransform' => 'uppercase'            )        )    );
    $settings['style_formats'] = json_encode( $style_formats );
    return $settings;
}

Running

WordPress 4.8.2 running With Gillion Child theme.