Why the $query->is_main_query() returning false (wordpress)

Question

I have a very simple index.php file in my wordpress myTheme folder where I want to show only the posts with "friends" category using the 'pre_get_posts' hook. But the $query->is_main_query() in the if condition is returning false. That's why it's not working, it's showing all the posts. Here is the code in my index.html file:

<?php
function myCategory( $query ) {
	if ( ! is_admin() && $query->is_main_query() && $query->is_search() ) {
		$query->set( 'category_name', 'friends' );
	}
}
add_action( 'pre_get_posts', 'myCategory' );


$paged = ( get_query_var( 'paged' ) ) ? get_query_var( 'paged' ) : 1;
$wp_query = new WP_Query( 'posts_per_page=2&paged='.$paged );
if ($wp_query->have_posts()) {
 	while ( $wp_query->have_posts() ) {
		$wp_query->the_post();
		echo "<h2><a href='".get_the_permalink()."'>".get_the_title()."</a></h2>";
		the_content("read more..",false);
	}
} 
previous_posts_link("<< Previous");
next_posts_link("More >>");

?>

But when I am using the following code just removing the $query->is_main_query() from the if condition inside the myCategory() function, it's working.

<?php
function myCategory( $query ) {
	if ( $query->is_home() && ! is_admin() ) {
		$query->set( 'category_name', 'friends' );
	}
}
add_action( 'pre_get_posts', 'myCategory' );


$paged = ( get_query_var( 'paged' ) ) ? get_query_var( 'paged' ) : 1;
$wp_query = new WP_Query( 'posts_per_page=2&paged='.$paged );
if ($wp_query->have_posts()) {
 	while ( $wp_query->have_posts() ) {
		$wp_query->the_post();
		echo "<h2><a href='".get_the_permalink()."'>".get_the_title()."</a></h2>";
		the_content("read more..",false);
	}
} 
previous_posts_link("<< Previous");
next_posts_link("More >>");

?>

Now, I want to know why the $query->is_main_query() is returning false. Could anyone explain please?

sticksu sticksu · Accepted Answer · 2017-11-03T10:11:22

From your examples I see that on the first one you are checking if it is a search page and on the second one you are checking is the page is home. So I would say that the problem is not the is_main_query() check, but the is_search() one, probably you are checking the changes on homepage and that's why it doesn't work.

Why the $query->is_main_query() returning false (wordpress)

1 Answers