in der single.php nur eine kategorie anzeigen?

<?php if ( have_posts() ) while ( have_posts() ) : the_post(); ?>


                <div id="nav-above" class="navigation">
                    
                </div><!-- #nav-above -->
                
                
                <div id="tagebuchwrapper">


                <div id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
                    <h1 class="entry-title"><?php the_title(); ?></h1>


                    <div class="entry-meta">
                        <?php twentyten_posted_on(); ?>
                    </div><!-- .entry-meta -->


                    <div class="entry-content">
                        <?php the_content(); ?>
                        <?php wp_link_pages( array( 'before' => '<div class="page-link">' . __( 'Pages:', 'twentyten' ), 'after' => '</div>' ) ); ?>
                    </div><!-- .entry-content -->


<?php if ( get_the_author_meta( 'description' ) ) : // If a user has filled out their description, show a bio on their entries  ?>
                    <div id="entry-author-info">
                        <div id="author-avatar">
                            <?php echo get_avatar( get_the_author_meta( 'user_email' ), apply_filters( 'twentyten_author_bio_avatar_size', 60 ) ); ?>
                        </div><!-- #author-avatar -->
                        <div id="author-description">
                            <h2><?php printf( esc_attr__( 'About %s', 'twentyten' ), get_the_author() ); ?></h2>
                            <?php the_author_meta( 'description' ); ?>
                            <div id="author-link">
                                <a href="<?php echo get_author_posts_url( get_the_author_meta( 'ID' ) ); ?>">
                                    <?php printf( __( 'View all posts by %s <span class="meta-nav">&rarr;</span>', 'twentyten' ), get_the_author() ); ?>
                                </a>
                            </div><!-- #author-link    -->
                        </div><!-- #author-description -->
                    </div><!-- #entry-author-info -->
<?php endif; ?>


                    <div class="entry-utility">
                        
                    </div><!-- .entry-utility -->
                </div><!-- #post-## -->
                
                </div><!-- #tagebuchwrapper -->


                <div id="nav-below" class="navigation">
                    <div class="nav-previous"><?php previous_post_link( '%link', '<span class="meta-nav">' . _x( '&larr;', 'Previous post link', 'twentyten' ) . '</span> %title' ); ?></div>
                    <div class="nav-next"><?php next_post_link( '%link', '%title <span class="meta-nav">' . _x( '&rarr;', 'Next post link', 'twentyten' ) . '</span>' ); ?></div>
                </div><!-- #nav-below -->


                


<?php endwhile; // end of the loop. ?>

<?php 
if (in_category('1')) { 
   include(TEMPLATEPATH . '/single_tagebuch.php');
// alle artikel aus kategorie 1


} elseif (in_category('6'))  { 
   include(TEMPLATEPATH . '/single_buchtipp.php'); 
// alle artikel aus kategorie 6   
   
} else { 
   // der stinkende rest
   include(TEMPLATEPATH . '/single_restmuell.php'); 
} 
?>