Fatal error when adding setting to customizer in wordpress - wordpress

Question

I am trying to add an extra setting in the Wordpress customizer. Can you add extra settings in the site title & tagline section or do you have to create your own section? This is the code I have so far in my functions.php file:
function mytheme_customize_register( $wp_customize )
{
$wp_customize->add_control(
new WP_Customize_Control(
$wp_customize,
'your_setting_id',
array(
'label' => __( 'Your Label Name', 'theme_name' ),
'section' => 'title_tagline',
'settings' => 'your_setting_id',
'type' => 'text'
)
)
);
}
add_action( 'customize_register', 'mytheme_customize_register' );
If I try to go to the customize theme page in the admin area though I get the following error:
Fatal error: Call to a member function check_capabilities() on a non-object in C:\xampp\htdocs\one-gas\wp-includes\class-wp-customize-control.php on line 161

Answer 1

Yes, you can add to the title and tagline section. Try using this code:
$wp_customize->add_control(
new WP_Customize_Control(
$wp_customize,
'your_setting_id',
array(
'label' => __( 'Your Label Name', 'theme_name' ),
'section' => 'title_tagline',
'settings' => 'your_setting_id',
'type' => 'text'
)
)
)
);
Read more about the Theme Customization API at the WordPress Codex.

Answer 2

I fixed it in the end it's because I had to define a setting first so this is the working code:
function mytheme_customize_register( $wp_customize )
{
$wp_customize->add_setting('subtagline', array(
'default' => 0,
'type' => 'option'
));
$wp_customize->add_control(
new WP_Customize_Control(
$wp_customize,
'subtagline',
array(
'label' => __( 'Sub Tagline', 'One Gas' ),
'section' => 'title_tagline',
'settings' => 'subtagline',
'type' => 'text'
)
)
);
}
add_action( 'customize_register', 'mytheme_customize_register' );