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Sure thank you. I’m kind of new to wordpress and I’m nervous with messing around with its code –

<?php
/**
 * WordPress Category API
 *
 * @package WordPress
 */

/**
 * Retrieves all category IDs.
 *
 * @since 2.0.0
 * @link http://codex.wordpress.org/Function_Reference/get_all_category_ids
 *
 * @return object List of all of the category IDs.
 */
function get_all_category_ids() {
	if ( ! $cat_ids = wp_cache_get( 'all_category_ids', 'category' ) ) {
		$cat_ids = get_terms( 'category', 'fields=ids&get=all' );
		wp_cache_add( 'all_category_ids', $cat_ids, 'category' );
	}

	return $cat_ids;
}

/**
 * Retrieve list of category objects.
 *
 * If you change the type to 'link' in the arguments, then the link categories
 * will be returned instead. Also all categories will be updated to be backwards
 * compatible with pre-2.3 plugins and themes.
 *
 * @since 2.1.0
 * @see get_terms() Type of arguments that can be changed.
 * @link http://codex.wordpress.org/Function_Reference/get_categories
 *
 * @param string|array $args Optional. Change the defaults retrieving categories.
 * @return array List of categories.
 */
function &get_categories( $args = '' ) {
	$defaults = array( 'type' => 'category' );
	$args = wp_parse_args( $args, $defaults );

	$taxonomy = apply_filters( 'get_categories_taxonomy', 'category', $args );
	if ( 'link' == $args['type'] )
		$taxonomy = 'link_category';
	$categories = (array) get_terms( $taxonomy, $args );

	foreach ( array_keys( $categories ) as $k )
		_make_cat_compat( $categories[$k] );

	return $categories;
}

/**
 * Retrieves category data given a category ID or category object.
 *
 * If you pass the $category parameter an object, which is assumed to be the
 * category row object retrieved the database. It will cache the category data.
 *
 * If you pass $category an integer of the category ID, then that category will
 * be retrieved from the database, if it isn't already cached, and pass it back.
 *
 * If you look at get_term(), then both types will be passed through several
 * filters and finally sanitized based on the $filter parameter value.
 *
 * The category will converted to maintain backwards compatibility.
 *
 * @since 1.5.1
 * @uses get_term() Used to get the category data from the taxonomy.
 *
 * @param int|object $category Category ID or Category row object
 * @param string $output Optional. Constant OBJECT, ARRAY_A, or ARRAY_N
 * @param string $filter Optional. Default is raw or no WordPress defined filter will applied.
 * @return mixed Category data in type defined by $output parameter.
 */
function &get_category( $category, $output = OBJECT, $filter = 'raw' ) {
	$category = get_term( $category, 'category', $output, $filter );
	if ( is_wp_error( $category ) )
		return $category;

	_make_cat_compat( $category );

	return $category;
}

/**
 * Retrieve category based on URL containing the category slug.
 *
 * Breaks the $category_path parameter up to get the category slug.
 *
 * Tries to find the child path and will return it. If it doesn't find a
 * match, then it will return the first category matching slug, if $full_match,
 * is set to false. If it does not, then it will return null.
 *
 * It is also possible that it will return a WP_Error object on failure. Check
 * for it when using this function.
 *
 * @since 2.1.0
 *
 * @param string $category_path URL containing category slugs.
 * @param bool $full_match Optional. Whether should match full path or not.
 * @param string $output Optional. Constant OBJECT, ARRAY_A, or ARRAY_N
 * @return null|object|array Null on failure. Type is based on $output value.
 */
function get_category_by_path( $category_path, $full_match = true, $output = OBJECT ) {
	$category_path = rawurlencode( urldecode( $category_path ) );
	$category_path = str_replace( '%2F', '/', $category_path );
	$category_path = str_replace( '%20', ' ', $category_path );
	$category_paths = '/' . trim( $category_path, '/' );
	$leaf_path  = sanitize_title( basename( $category_paths ) );
	$category_paths = explode( '/', $category_paths );
	$full_path = '';
	foreach ( (array) $category_paths as $pathdir )
		$full_path .= ( $pathdir != '' ? '/' : '' ) . sanitize_title( $pathdir );

	$categories = get_terms( 'category', "get=all&slug=$leaf_path" );

	if ( empty( $categories ) )
		return null;

	foreach ( $categories as $category ) {
		$path = '/' . $leaf_path;
		$curcategory = $category;
		while ( ( $curcategory->parent != 0 ) && ( $curcategory->parent != $curcategory->term_id ) ) {
			$curcategory = get_term( $curcategory->parent, 'category' );
			if ( is_wp_error( $curcategory ) )
				return $curcategory;
			$path = '/' . $curcategory->slug . $path;
		}

		if ( $path == $full_path )
			return get_category( $category->term_id, $output );
	}

	// If full matching is not required, return the first cat that matches the leaf.
	if ( ! $full_match )
		return get_category( $categories[0]->term_id, $output );

	return null;
}

/**
 * Retrieve category object by category slug.
 *
 * @since 2.3.0
 *
 * @param string $slug The category slug.
 * @return object Category data object
 */
function get_category_by_slug( $slug  ) {
	$category = get_term_by( 'slug', $slug, 'category' );
	if ( $category )
		_make_cat_compat( $category );

	return $category;
}

/**
 * Retrieve the ID of a category from its name.
 *
 * @since 1.0.0
 *
 * @param string $cat_name Optional. Default is 'General' and can be any category name.
 * @return int 0, if failure and ID of category on success.
 */
function get_cat_ID( $cat_name='General' ) {
	$cat = get_term_by( 'name', $cat_name, 'category' );
	if ( $cat )
		return $cat->term_id;
	return 0;
}

/**
 * Retrieve the name of a category from its ID.
 *
 * @since 1.0.0
 *
 * @param int $cat_id Category ID
 * @return string Category name
 */
function get_cat_name( $cat_id ) {
	$cat_id = (int) $cat_id;
	$category = &get_category( $cat_id );
	return $category->name;
}

/**
 * Check if a category is an ancestor of another category.
 *
 * You can use either an id or the category object for both parameters. If you
 * use an integer the category will be retrieved.
 *
 * @since 2.1.0
 *
 * @param int|object $cat1 ID or object to check if this is the parent category.
 * @param int|object $cat2 The child category.
 * @return bool Whether $cat2 is child of $cat1
 */
function cat_is_ancestor_of( $cat1, $cat2 ) {
	if ( ! isset($cat1->term_id) )
		$cat1 = &get_category( $cat1 );
	if ( ! isset($cat2->parent) )
		$cat2 = &get_category( $cat2 );

	if ( empty($cat1->term_id) || empty($cat2->parent) )
		return false;
	if ( $cat2->parent == $cat1->term_id )
		return true;

	return cat_is_ancestor_of( $cat1, get_category( $cat2->parent ) );
}

/**
 * Sanitizes category data based on context.
 *
 * @since 2.3.0
 * @uses sanitize_term() See this function for what context are supported.
 *
 * @param object|array $category Category data
 * @param string $context Optional. Default is 'display'.
 * @return object|array Same type as $category with sanitized data for safe use.
 */
function sanitize_category( $category, $context = 'display' ) {
	return sanitize_term( $category, 'category', $context );
}

/**
 * Sanitizes data in single category key field.
 *
 * @since 2.3.0
 * @uses sanitize_term_field() See function for more details.
 *
 * @param string $field Category key to sanitize
 * @param mixed $value Category value to sanitize
 * @param int $cat_id Category ID
 * @param string $context What filter to use, 'raw', 'display', etc.
 * @return mixed Same type as $value after $value has been sanitized.
 */
function sanitize_category_field( $field, $value, $cat_id, $context ) {
	return sanitize_term_field( $field, $value, $cat_id, 'category', $context );
}

/* Tags */

/**
 * Retrieves all post tags.
 *
 * @since 2.3.0
 * @see get_terms() For list of arguments to pass.
 * @uses apply_filters() Calls 'get_tags' hook on array of tags and with $args.
 *
 * @param string|array $args Tag arguments to use when retrieving tags.
 * @return array List of tags.
 */
function &get_tags( $args = '' ) {
	$tags = get_terms( 'post_tag', $args );

	if ( empty( $tags ) ) {
		$return = array();
		return $return;
	}

	$tags = apply_filters( 'get_tags', $tags, $args );
	return $tags;
}

/**
 * Retrieve post tag by tag ID or tag object.
 *
 * If you pass the $tag parameter an object, which is assumed to be the tag row
 * object retrieved the database. It will cache the tag data.
 *
 * If you pass $tag an integer of the tag ID, then that tag will
 * be retrieved from the database, if it isn't already cached, and pass it back.
 *
 * If you look at get_term(), then both types will be passed through several
 * filters and finally sanitized based on the $filter parameter value.
 *
 * @since 2.3.0
 *
 * @param int|object $tag
 * @param string $output Optional. Constant OBJECT, ARRAY_A, or ARRAY_N
 * @param string $filter Optional. Default is raw or no WordPress defined filter will applied.
 * @return object|array Return type based on $output value.
 */
function &get_tag( $tag, $output = OBJECT, $filter = 'raw' ) {
	return get_term( $tag, 'post_tag', $output, $filter );
}

/* Cache */

/**
 * Update the categories cache.
 *
 * This function does not appear to be used anymore or does not appear to be
 * needed. It might be a legacy function left over from when there was a need
 * for updating the category cache.
 *
 * @since 1.5.0
 *
 * @return bool Always return True
 */
function update_category_cache() {
	return true;
}

/**
 * Remove the category cache data based on ID.
 *
 * @since 2.1.0
 * @uses clean_term_cache() Clears the cache for the category based on ID
 *
 * @param int $id Category ID
 */
function clean_category_cache( $id ) {
	clean_term_cache( $id, 'category' );
}

/**
 * Update category structure to old pre 2.3 from new taxonomy structure.
 *
 * This function was added for the taxonomy support to update the new category
 * structure with the old category one. This will maintain compatibility with
 * plugins and themes which depend on the old key or property names.
 *
 * The parameter should only be passed a variable and not create the array or
 * object inline to the parameter. The reason for this is that parameter is
 * passed by reference and PHP will fail unless it has the variable.
 *
 * There is no return value, because everything is updated on the variable you
 * pass to it. This is one of the features with using pass by reference in PHP.
 *
 * @since 2.3.0
 * @access private
 *
 * @param array|object $category Category Row object or array
 */
function _make_cat_compat( &$category ) {
	if ( is_object( $category ) ) {
		$category->cat_ID = &$category->term_id;
		$category->category_count = &$category->count;
		$category->category_description = &$category->description;
		$category->cat_name = &$category->name;
		$category->category_nicename = &$category->slug;
		$category->category_parent = &$category->parent;
	} elseif ( is_array( $category ) && isset( $category['term_id'] ) ) {
		$category['cat_ID'] = &$category['term_id'];
		$category['category_count'] = &$category['count'];
		$category['category_description'] = &$category['description'];
		$category['cat_name'] = &$category['name'];
		$category['category_nicename'] = &$category['slug'];
		$category['category_parent'] = &$category['parent'];
	}
}

?>

You’re totally awesome –

Amanda

My bad 🙂

Here’s archive.php. There’s no category.php. I’m using default by anonymous.

Here’s the code

I pasted the code in archive.php but it didn’t work 🙁

Yes, that’s what I’m trying to do. I want the posts in the parent category only to be shown in the parent category, and the posts from the child cats to be shown in the child cats only, not parent cat.

I’m using this Fold Category List. It has different features than FoCal, which didn’t work for me.

It could be that the php in the fold category list is overriding what you wrote. Any other suggestions then? Does the php you gave me work with FoCal? I can install that again and see if I can work around it.

I tried playing around with different plugins but nothing helped. Do you think if I create a separate category page for parent categories that would help? Can I use your code on an exclusive page just for parent categories and then call the other category page for the child cats? If yes, how would I go about it?

You’re a lifesaver Jacob, thanks for giving me the time!!

Amanda

Really odd – I created a new page called category.php and it’s still not working. All posts are showing up. Am I supposed to be changing anything else?

Here is my header.php, footer.php and functions.php.

Thank you!