It is very useful to show some random posts after the current reading post. You online need one litle function for that:

Code block

function get_random_posts ($number_of_posts) {
global $wpdb, $post;
$current_post = get_the_title();
$random_posts = $wpdb->get_results("SELECT $wpdb->posts.ID, \
post_title, post_name, post_date, post_type, post_status FROM \
$wpdb->posts WHERE post_type = 'post' AND post_status = 'publish' \
AND post_title != '$current_post' ORDER BY RAND() limit \
$number_of_posts");
foreach ($random_posts as $post) {
$post_title = htmlspecialchars(stripslashes($post->post_title));
echo "<li><a href=\"".get_permalink()."\">$post_title</a></li>";
}
}

How this works?

1. Get the current post title with “$current_post = get_the_title();” because, we won’t show this title again
2. Get x random posts “…$random_posts = $wpdb->get_results…”
3. Go trought each post, get its title and show it “foreach ($random_posts as $post)…”

That’s all! Have Fun!

]]> http://coding.my-guide.org/wordpress/how-to-show-random-posts-after-current-post/feed/ 0 http://coding.my-guide.org/wordpress/change-autosave-interval-and-limit-revisions/ http://coding.my-guide.org/wordpress/change-autosave-interval-and-limit-revisions/#comments Mon, 16 Mar 2009 11:28:38 +0000 Bako http://coding.my-guide.org/?p=33 Difficulty Level:

Today we will show you how to change auto save time interval in wordpress and how to limit post revisions.  This is very simple. You only have to change your wp-config.php

To change auto save interval you have to put this line in your wp-config.php:

Code block

define(’AUTOSAVE_INTERVAL’, [DURATION_IN_SECONDS]);

Replace [DURATION_IN_SECONDS] with your desired number of seconds.

To limit revision posts you have to put this line into your wp-config.php:

Code block

define (’WP_POST_REVISIONS’, [NUMBER_OF_REVISION]);

If you replace [NUMBER_OF_REVISION] with “0″ (zero), no more revisions will be saved. Otherwise replace [NUMBER_OF_REVISION] with your desired number of revisions for each post.

Sometimes it is usefull to display other information on your main blog page. WordPress provides a conditional tag called “is_home()”. This tag detects if you are on the main blog page, so you are able to display other or more information on the main blog page.

Code block

<?php
// Check if you are on the main page
if (is_home()){
// get all catogery id's
$catIDs = get_all_category_ids();
// get all post with the first category id
query_posts('cat=' . $catIDs[0]);
}
?>

Description:

1. We use the conditional tag “is_home()” to detect if we are on the main page.
2. Then we get all category id’s.
3. We look for posts with the first category id.

You can download this example here.

On this tutorial I will show you how to make this on your wordpress index page:

If you wish to show a defined number of posts from each category on your index page, you can do it like this:

Code block

<?php
global $post;
$categories = get_categories();
foreach ($categories as $category) {
$cat_id = $category->cat_ID;
$games = get_posts('numberposts=6&orderby=rand&category='.$cat_id);
if ($games) {
echo '<div class="category">';
echo '<h1><a href="'.get_category_link($cat_id).'">' \
.$category->name. '</a></h1>';
foreach ($games as $post) {
?>
<div class="game_title">
<a href="<?php the_permalink() ?>" rel="bookmark"  \
title="<?php the_title(); ?>" >
<?php if ((strlen($post->post_title) > 10)) { \
echo substr($post->post_title, 0, 10).".."; } else the_title(); ?>
<br>
<img src = "<?php echo get_post_meta($post->ID, "thumbnail_url", \
true);
?>" width="85" height="85"></a>
</div>
<?php
}
echo '<div class="cat_link"><a href="'.get_category_link($cat_id).'">
\ More Games</a></div>';
echo '</div>';
}
}
?>

Explanation:

• Get all categories: “$categories = get_categories(); “
• Go trough each category and get 6 random posts: “foreach ($categories as $category)” … “get_posts(‘numberposts=6&orderby=rand&category=’.$cat_id);”
• Get each post and show it: “foreach ($games as $post)” …

You can download this example here:

If you have a apache webserver running on a linux machine sometimes it happens that the webserver crashs. This could have many reasons, but still there is the problem your site isn’t reachable. How can we solve this problem?

An easy way to check the apache deamon is in wiriting a small bash script. You can run the script every hour in a cron job.

So what is this script doing?

1. First we check if the apache deamon is running.
2. If the apache deamon is running we do nothing.
3. If the apache deamon isn’t running we start the deamon again.
4. After the start, we check again if the deamon was successfully started

Code block

# look if the apache deamon is running
apacha_alive=`ps -eaf |grep apache2 |grep -v grep |wc -l`
if [ "$apacha_alive" -lt "1" ]; then
# Apache is not running
# Start Apache Deamon
/etc/init.d/apache2 start
# Check if start was successful
apacha_alive=`ps -eaf |grep apache2 |grep -v grep |wc -l`
if [ "$apacha_alive" -lt "1" ]; then
echo "Apache couldn't be started"
else
echo "Apache successfully started"
fi
else
echo "Apache is already running"
fi

You can also download this bash script.

Hello and welcome to a new small tutorial about wordpress-mu plugins. This tutorial is build on a previous tutorial “How to use a plugin function in a post?“. The main focus is to how to create a nice table to present your themes in a gallery.

So this is what you need:

Function 1:

Code block

function mg_show_gallery_available_themes($match) {
//Clear output
$output ='';
$colcount   = 2;
// picture settings
$imgwidth   = 'width="300px"';
$imgheight  = 'height="225px"';
$cellheight = 'height="250px"';
// Get all theme information
$themes       = get_themes();
// count the available themes
$theme_total  = count( $themes );
$theme_names  = array_keys($themes);
// Calculate the necessary rows
$rows = ceil(count($theme_names) / $colcount);
for ( $row = 1; $row <= $rows; $row++ ) {
for ( $col = 1; $col <= $colcount; $col++ ) {
$table[$row][$col] = array_shift($theme_names);
}
}
// table "START"
$output .= '<table width="100%" border="0"
cellspacing="5" cellpadding="0">';
foreach ( $table as $row => $cols )
{
$output .= '<tr align="center" ' . $cellheight . '>';
foreach ( $cols as $col => $theme_name ) {
$class = array('available-theme');
// Define the postion
if ( $row == 1 ) $class[] = 'top';
if ( $col == 1 ) $class[] = 'left';
if ( $row == $rows ) $class[] = 'bottom';
if ( $col == 3 ) $class[] = 'right';
$output .= '<td class="'. join(' ', $class) . $cellwidth . '">';
if ( !empty($theme_name) ) :
$template = $themes[$theme_name]['Template'];
$title = $themes[$theme_name]['Title'];
$screenshot = $themes[$theme_name]['Screenshot'];
$stylesheet_dir = $themes[$theme_name]['Stylesheet Dir'];
$thickbox_class = 'thickbox';
// Write theme name
$output .= '<h3>' . $title . '</h3>';
// Build your image link to a screenshot
if ( $screenshot )
{
$output .= '<image src="' .WP_CONTENT_URL . $stylesheet_dir .
'/' . $screenshot .'?>"' . $imgwidth . $imgheight .'alt="'.
$title .'">';
}
// There is no screenshot available
else
{
$output .= 'No screenshot available..';
}
endif;
$output .= '</td>';
}
$output .= '</tr>';
}
// table "END"
$output .= '</table>';
return($output);
}

Function 2:

Code block

/***H*O*O*K******************************************/
add_filter('the_content', 'embeddedshow_list_available_themes');
/****************************************************/
// actual plugin function
function embeddedshow_list_available_themes($content) {
$output = preg_replace_callback('[mg_call_show_list_available_themes]'
,'mg_show_gallery_available_themes', $content);
return ($output);
}

1. We define setting for the table. How big are the thumbnails in you gallery and how many columns we want to have.
2. Now we have to look how much themes are available and calculate how much rows we will need.
3. Start creating the rows and columns and filling the cells of the table with the theme name and screenshot thumbnail.
4. If there is no screenshot available we will show a “No screenshot available..” message.
5. Ending the table.
6. The last thing you have to do is to insert the string “mg_call_show_gallery_available_themes” in a post.

Result:

You can also download this wordpress mu plugin.

I was looking for a solution to crack this problem. Unfortunately I didn’t found a anything appropriate. So I created a simple tool. This tool scans a directory which contains your theme collection and creates a HTML page with all thumbnails. So I don’t have to upload all themes to my server only to look over all thumbnails. I call it “WordPress Theme Preview Maker”!

You can download and use “WordPress Theme Preview Maker” for free. You can share it with your friends or others. Do not SELL!

To run WordPress Theme Preview Maker you need Microsoft .NET Framework.

Today we will show you how to use your own plugin function in a post.

Sometimes you want to add special content to your post, but there is no wordpress function available. An easy way to solve this problem is to write your own function, which will do what you want and include it into your post with a special tag. In our example we will use a function which shows a list of all available themes.

In four small steps we will reach our goal:

Step 1:
Create a php file. Name it “mg_plugin_post.php”.

Step 2:
Now you have to insert this two small functions:

Funtion 1:

Code block

function mg_show_list_available_themes($match) {
//Clear output
$output ='';
// Get all theme information
$themes   = get_themes();
// Get all Theme names
$theme_names  = array_keys($themes);
// Create the output
$output = 'List of all available themes:';
$output .= '<ul>';
//Write every theme name in a list element
foreach($theme_names as $my_themes)
$output .= '<li>' .$my_themes .'</li>';
$output .= '</ul>';
// Return the whole output string
return($output);
}

Code block

/***H*O*O*K*************************************/
add_filter('the_content', 'embeddedshow_list_available_themes');
/***********************************************/
// actual plugin function
function embeddedshow_list_available_themes($content) {
$output=preg_replace_callback('[mg_call_show_list_available_themes]',
'mg_show_list_available_themes', $content);
return ($output);
}

Step 3:
Copy this file in your mu-plugins directory.

Step 4:
Create a new post and the content of your post will be mg_call_show_list_available_themes.

Now you will get a list of all themes in your post.

How did we do that?

1. In “Function 2″ we use a filter to call a function embeddedshow_list_available_themes when content of your blog will be generated.
2. In this function we use the php function preg_replace_callback to search the content for the special string mg_call_show_list_available_themes. So if we find that string we will call a new function.
3. In this case the “Function 1″ mg_show_list_available_themes which will generate the list of all available themes and return it to “Function 2″.
4. The funtion embeddedshow_list_available_themes replaces the string mg_call_show_list_available_themes in your post with the new content generated by “Function 1″.

You can also download this wordpress mu plugin.

How should it work?

• Create a menu entry
• Check if the user has enough rights to run this script
• Get a list of all blogs
• Go to each post table and delete posts marked as “revision”

Create a menu entry

First you have to create a file named “mg_clean_revisions.php”. Open the file to put some code into it. At first we need a hook which will be called when you access the admin menu. This hook should run a function which creates a menu entry.

Code block

// H O O K
add_action('admin_menu', 'mg_clean_revisions_menu');
// Create menu entry
function mg_clean_revisions_menu() {
add_submenu_page('wpmu-admin.php', 'Clean Revisions',
'Clean Revisions', 1, 'mg_clean_revisions.php', 'mg_clean_revisions');
}

A menu entry “Clean Revisions” will be created. When you click on this menu, the script will call a function named “mg_clean_revisions”. Now we have to implement this function. When this function is called we should check if the user has enough access rights to do this. Then we need a list of all blogs that we can delete posts marked as “revision”.

Code block

function mg_clean_revisions() {
global $wpdb;
echo "<h1>My-Guide's Clean Revisions</h1>";
// Check Whether User Can Manage Database
if(!current_user_can('manage_database')) {
die('Access Denied');
}
// Get all blogs
$blog_list = $wpdb->get_results( "SELECT blog_id FROM $wpdb->blogs");
// Go trough all blogs and delete revisions
foreach ($blog_list as $blog) {
$table = $wpdb->base_prefix . $blog->blog_id . '_posts';
$wpdb->query("DELETE FROM $table WHERE post_type = 'revision'");
print "Cleaning: " . $table . " ..done<br>";
}
echo "<br><strong>All revisions deleted.</strong>";
}

This is very simple. All we have to do is to replace the background image at <h1> stylesheet. Let’s go:

Create a new css file. I will name this file “mg_login_style.css”. Add this few lines:

Code block

h1 a {
background: url(mg_login_logo.png) no-repeat top center;
width: 326px;
height: 50px;
text-indent: -9999px;
overflow: hidden;
padding-bottom: 15px;
display: block;
}

Now, you have to create your own logo with transparent background. Name your logo “mg_login_logo.png”, because we’ve defined it’s name at this line:

Code block

background: url(mg_login_logo.png) no-repeat top center;

At this moment, you should have two files, one logo image and one css-file. Finaly, you have to create a hook to replace the original logo. We need a new file. Name it “mg_login.php”. This php script contains one function, which prints your css file into login page and one hook which is called, when someone will login.

The code below shows, how it works on wordpress mu (wpmu). For “normal” wordpress you have to replace “mu-plugins” with “plugins”.

Code block

function mg_login() {
$csslocation = get_settings('siteurl')
. '/wp-content/mu-plugins/mg_login_style.css';
// print the css file
echo '<link rel="stylesheet" type="text/css" href="'
. $csslocation . '" />';
}
/* H O O K */
add_action('login_head', 'mg_login');

Here you can download this wordpress mu plugin: