WordPress Logic: If Is Logged In

There are several tidbits of code that I have collected over the past few years that make it easier and easier to turn a simple WordPress installation into a very functional content management system (CMS). There are many times when it would be nice to show logged in members certain bits of information (certain categories, posts, or just a simple “Welcome back!”) and of course there is a simple way of doing this:

<?php if ( is_user_logged_in() ) echo 'Welcome back!';?>

That bit of code will allow you to do something like this which will allow you to show the logged in user’s preferred user name (selected in the User preferences), and then a list of member only pages (private page parent is page ID 20 – I am showing all sub pages of the members-only pages marked as private). If the user is not logged in, they will get a Welcome visitor! greeting :

<?php
if ( is_user_logged_in() ) :
  global $current_user;
  get_currentuserinfo();
?>	
  <p>Welcome back <?php echo esc_html( $current_user->display_name );?></p>
  <p>Here is a list of private pages only viewable by Members:</p>
  <ul>
  <?php wp_list_pages('post_status=publish,private&child_of=20');?>		
  </ul>
<?php else : ?>
  <p>Welcome, visitor!</p>
<?php endif;?>

You can make it as simple as a change in greeting for members and non-members, or put in specific logic like I did with showing the pages. The potential is limitless.

Search Specific Category in WordPress

There are some times when you want to limit your search to a particular category, or perhaps multiple categories. This is relatively simple to do in WordPress by adding a hidden field to your search code. (See example below)

<form method="get" id="search form" action="/">
<div>
<input type="text" value="" name="s" id="s" />
<input type="hidden" value="22" name="cat" id="scat" />
<input type="submit" id="search_submit" name="Search" value="Search"/>
</div>
</form>

You can see I added my hidden input field on the third line. When I add this in, it then adds onto the query used to search. Your search will go from something like http://jzelazny.wpengine.com/?s=WordPress to http://jzelazny.wpengine.com/?s=WordPress&cat=22 and will only return posts in the category ID you choose.

Highlighted Navigation with WordPress

Ever wonder how to automatically highlight your tabs or navigation depending on the category, page, or post you are on? Wonder no more! To make this work, there are three bits of code you will need:

  • The header code to control the body ID (and to tell us what page we are on)
  • The navigation code
  • The CSS to control the highlight

For this example, I will use this web site as an example.

The header code

ID;
$parent = 1;
while($parent) {
$page_query = $wpdb-&gt;get_row("SELECT post_name, post_parent FROM $wpdb-&gt;posts WHERE ID = '$current_page'");
$parent = $current_page = $page_query-&gt;post_parent;
if(!$parent)
$parent_name = $page_query-&gt;post_name;
}
?&gt;

&lt;body id=&quot;"&gt;

The XHTML code (navigation)

<div>
<ul>
<li><a href="/index.php">Home</a></li>
<li><a href="/blog/">SDAC Blog</a></li>
<li><a href="/web_solutions/">Web Solutions</a></li>
<li><a href="/network_solutions/">Network Solutions</a></li><li><a href="/user_interface_solutions/">User Interface Solutions</a></li>
<li><a href="/custom_solutions/">Custom Solutions</a></li>
<li><a href="/search/">Search</a></li>
</ul>
</div>

The CSS code

#home #nav-home, #about_us #nav-home, #contactus #nav-home, #faqs #nav-home, 
#disclaimer #nav-home, #search #nav-search, 
#blog #nav-blog, #web_solutions #nav-websolutions, #network_solutions #nav-networksolutions, 
#user_interface_solutions #nav-userinterfacesolutions, 
#custom_solutions #nav-customsolutions, #tos #nav-home, #sitemap #nav-home {
	  background:url("images/tabs/active_tab_bg.gif") repeat-x;
      border-right:1px solid #676e78;
      }
          
#tabs li:hover, #tabs li:hover a {
	background: url("images/tabs/active_tab_bg.gif") repeat-x;
    color:#212933;
    }

General information
When you view the code for a page, you will notice that the header code will find out if the page viewed is infact a page. If it is a page, it gets the page parent (I use parent and child pages in my web site organization). The tabs are created with unique li IDs. So that a combination of #home (the body ID) and the #nav-home (li ID) will show as a highlighted tab. With this example, this case will only occur when we are on the home page because #home is a page (the home page) so the home tab will be highlighted. When we click on “SDAC Blog”, the body ID will then be #blog, so now the #blog #nav-blog combination will force the “SDAC Blog” tab to be highlighted. Take a look at the CSS to see where to define the “cases”.

Hopefully this took some of the mystery out of working with WordPress, navigation, and how to put everything together.