Note that there's no is_admin() method offor the WP_Query class.
But the interesting part is that PHP will not complain about this:
$query->is_admin()
where $query is an instance of WP_Query.
It will just always return false.
This is the reason why (src#src):
/**
* Make private/protected methods readable for backwards compatibility.
*
* @since 4.0.0
* @access public
*
* @param callable $name Method to call.
* @param array $arguments Arguments to pass when calling.
* @return mixed|false Return value of the callback, false otherwise.
*/
public function __call( $name, $arguments ) {
if ( in_array( $name, $this->compat_methods ) ) {
return call_user_func_array( array( $this, $name ), $arguments );
}
return false;
}
The magic __call method, kicks in when you call the non-existent method is_admin(). This is from the PHP documentation:
__call()is triggered when invoking inaccessible methods in an object context.
The magic __call method, kicks in when we call the non-existent method is_admin().
I assume you're hooking into the pre_get_posts action.
We can use the is_admin() check:
add_action( 'pre_get_posts', function( \WP_QUery\WP_Query $query )
{
// Only on the front-end
if( is_admin() )
return;
// ... your stuff here ...
} );
or we could use the is_admin public attribute of the WP_Query instance:
add_action( 'pre_get_posts', function( \WP_QUery\WP_Query $query )
{
// Only on the front-end
if( $query->is_admin )
return;
// ... your stuff here ...
} );
where it in fact usesit's based on the is_admin() function, in the parse_query() method (src#src):
if ( is_admin() )
$this->is_admin = true;