In this guide, we are going to create a simple plugin that scan through the post content for “{donationcode}” and replace it with our paypal donation codes. Jump to complete code

1. Creating a new plugin php file

We created a file called simple_replacer.php and put it into wp-content/plugins/simple_replacer/ folder.

2. The plugin header

<?php
/*
Plugin Name: Simple Replacer
Plugin URI: link to your page to download the plugin or usage guide
Description: Replaces {donationcode} with paypal donation codes
Author: Zen
Version: 1.0
Author URI: http://zenverse.net/
*/
 
?>

3. Adding a function that does the replacing work

Type these codes into the file after the header part (after */)

function the_replacer($content) {
 
$post = str_replace( '{donationcode}' , 'YOUR_DONATION_HTML_CODES' , $content);
 
return $content;
}

NOTE:
Without returning the variable $content, you will ruin the whole post content (return empty content), so make sure you include the “return” line.

4. Adding filter, let wordpress know what we want to do

Add this, 1 line before the php closing tag (?>)

add_filter('the_content', 'the_replacer');
 
//if you want to run the function on excerpts too, uncomment the line below
//add_filter('the_excerpt', 'the_replacer');

NOTE:
The function name “the_replacer” must match the php function that you created in step 3.

The Complete Code

<?php
/*
Plugin Name: Simple Replacer
Plugin URI: link to your page to download the plugin or usage guide
Description: Replaces {donationcode} with paypal donation codes
Author: Zen
Version: 1.0
Author URI: http://zenverse.net/
*/
 
function the_replacer($content) {
 
$post = str_replace( '{donationcode}' , 'YOUR_DONATION_HTML_CODES' , $content);
 
return $content;
}
 
 
add_filter('the_content', 'the_replacer');
 
//if you want to run the function on excerpts too, uncomment the line below
//add_filter('the_excerpt', 'the_replacer');
 
?>

That’s it.

1. Adding codes to The Loop

First of all, if you do not know what is The Loop, please refer to this page.

Open up index.php, look for:

<?php the_excerpt(); ?>

or, your theme may be using this instead of that above:

<?php the_content(); ?>

Add these codes just before the “the_excerpt” or “the_content” line :

<?php if (function_exists('has_post_thumbnail')) {
 if ( has_post_thumbnail() ) { ?>
	<a href="<?php the_permalink(); ?>"><?php the_post_thumbnail( array( 150, 150 ), array( 'class' => 'alignleft') ); ?></a>
<?php } } ?>

Explaination:

• The first line check whether “has_post_thumbnail” function exists before running the code, so that it wouldn’t causes fatal error in older wordpress version.
• has_post_thumbnail is the function that determine whether your post has post thumbnail
• the_post_thumbnail is the function that output the post thumbnail <img> tag

.

2. Using the_post_thumbnail()

According to the wordpress codex, the function’s usage is:

<?php the_post_thumbnail( $size, $attr ); ?>

It can accept 2 arguments. The first argument is the thumbnail size and the second argument is the image’s attributes.

Based on the example in part 1
I used to specify the thumbnail size in array form, like in the above example (a square thumbnail of 150 pixels).

For the second argument, I added .alignleft class to the thumbnail so that it floats left. You can add more attributes like this too:

the_post_thumbnail( array( 150, 150 ), array( 'class' => 'alignleft' , style' => 'border:1px solid red ; margin-right:5px ;' ) );

3. Make your theme support post thumbnail

Open functions.php, scroll to the most bottom and add this before ?> (the closing php tag) :

if ( function_exists( 'add_theme_support' ) ) {
add_theme_support( 'post-thumbnails' );
}

Visit your admin panel and edit/create a post, you will then notice a new box called “Post Thumbnail” appear at the bottom right corner. You can add thumbnail there.

4. I need rectangle thumbnail

When you upload a thumbnail, wordpress generates only square thumbnails. What if you need rectangle thumbnail in your theme?

In your functions.php, look for:

add_theme_support( 'post-thumbnails' );

After that, add this in the next line:

set_post_thumbnail_size( 300, 100, true );

The first argument is width, second is height and the third is crop_flag (if true, wordpress will crop it upon creating the thumbnail, instead of resizing)

From now on, wordpress will generate an additional rectangle thumbnail of size 300 x 100 pixels everytime you upload image.

Okay, you might ask, what about my old uploaded images? I want each of them to have a rectangle thumbnail too. Fortunately, there is a plugin called “Regenerate Thumbnails” which can do the job for you automatically.

Hope this helps

<?php if ( has_post_image() ) { ?>
	<a href="<?php the_permalink(); ?>"><?php the_post_image( array( 125, 125 ), array( 'class' => 'alignleft' ) ); ?></a>
<?php } ?>

However, the function names above were based on wordpress 2.9 RC1. The functions names actually changed when Wordpress 2.9 is out.

• has_post_image() -> has_post_thumbnail()
• the_post_image() -> the_post_thumbnail()

So the codes you need to use is:

<?php if ( has_post_thumbnail() ) { ?>
	<a href="<?php the_permalink(); ?>"><?php the_post_thumbnail( array( 125, 125 ), array( 'class' => 'alignleft' ) ); ?></a>
<?php } ?>

That’s it.

There are 2 functions available :

• wptdb_output()
• wptdb_list_themes()

Function : wptdb_output()

Please read ” Using shortcode ” first to understand this page better.

Description

Allows you to output theme info in template files instead of using shortcode in post. It accepts argument in strings and works exactly like the shortcode . Introduced in version 1.4.

Usage

<?php 
if ( function_exists ( 'wptdb_output' ) ) {
wptdb_output($args);
}
?>

Parameters

theme
(string) The theme’s folder name. Must be set.

format
(string) Format id. Default format will be used if you give an invalid format id.

get
(string) Get single info instead of using format.
Valid values : All available tags

autop
(string) Auto wrap the content with HTML paragraph <p> tag

• true – default
• false / 0 (to display content inline)

echo
(string) Show the result or keep it in a variable. Default is true.

• 1 (true) – default
• 0 (false)

Example of Usage

Display format id of 1

<?php 
if ( function_exists ( 'wptdb_output' ) ) {
wptdb_output( 'theme=my-theme-folder-name&format=1' );
}
?>

Display number of previews (inline)

Lunated theme has <?php 
if ( function_exists ( 'wptdb_output' ) ) {
wptdb_output( 'theme=lunated&get=hits&autop=false' );
}
?> previews in total.

Assign to variable

<?php 
if ( function_exists ( 'wptdb_output' ) ) {
$stored = wptdb_output( 'theme=lunated&get=today&echo=0' );
echo $stored;
}
?>

Argument in array form

<?php 
if ( function_exists ( 'wptdb_output' ) ) {
$stored = wptdb_output( array(
'theme' => 'lunated',
'get' => 'today',
'echo' => '0',
) );
echo $stored;
}
?>

Function : wptdb_list_themes()

Description

Allows you to display a drop-down menu (<select>) for visitors to choose and preview your non-private themes. Introduced in version 1.5

Usage

<?php 
if ( function_exists ( 'wptdb_list_themes' ) ) {
wptdb_list_themes($args);
}
?>

Parameters

style
(string) Type of output. Default is “option” which output <option> to be used with <select>. Valid values:

• option – default

hierarchical
(string) Show parent-child relationship. Default is true. Valid values:

• 1 / true (true) – default
• 0 / false (false)

orderby
(string) Sort themes by wordpress default method or by number of previews. Valid values:

• default – default
• hits

order
(string) Sort order for themes (either ascending or descending). Default is asc. Valid values:

• asc – default
• desc

show_hits
(string) Show number of previews beside theme name in a bracket. Default is false. Valid values:

• true / 1
• false / 0 – default

echo
(string) Show the result or keep it in a variable. Default is true.

• 1 (true) – default
• 0 (false)

Example of Usage

Display drop-down menu using default settings

<?php 
if ( function_exists ( 'wptdb_list_themes' ) ) {
echo '<select name="">';
wptdb_list_themes();
echo '</select>';
}
?>

Display drop-down menu , sort the themes by number of previews in descending order

<?php 
if ( function_exists ( 'wptdb_list_themes' ) ) {
echo '<select name="">';
wptdb_list_themes( 'orderby=hits&order=desc' );
echo '</select>';
}
?>

Display drop-down menu with number of previews shown beside the theme name

<?php 
if ( function_exists ( 'wptdb_list_themes' ) ) {
echo '<select name="">';
wptdb_list_themes( 'show_hits=1' );
echo '</select>';
}
?>

Argument in array form

<?php 
if ( function_exists ( 'wptdb_list_themes' ) ) {
echo '<select name="">';
wptdb_list_themes( array(
'orderby' => 'hits',
'order' => 'desc',
));
echo '</select>';
}
?>

What can you do with shortcode ?

You can display theme info such as number of previews in posts and pages. You can output anything within these supported tags:

• Name of the theme (based on style.css)
• Description of the theme (based on style.css)
• Theme URI (based on style.css)
• Author name (based on style.css)
• Version number of the theme (based on style.css)
• Folder name of the theme
• URL to preview the theme (?themedemo=xxx)
• Total no. of previews
• URL to theme’s screenshot file
• URL to the theme’s info page (if exist)
• URL to the theme’s download page (if exist)
• URL to the page to buy the theme (if exist)

Example of what you can do

Retrieve the number of previews of my Lunated Theme and display it inline

Oh. Lunated theme has been previewed 13630 times in total.

Make a preview link to Lunated theme using default format

Preview Lunated (13630)

Understanding and Using Shortcode

Generally, you need to specify the theme folder name like:

To understand more about the shortcode and examples:

1. Get Single Info only

Use attribute ‘get’ to return only a single infomation

Valid values of attribute ‘get’ :
All tags available are the valid values of attribute ‘get’. However, you can only use one tag at once. (without curly bracket of course)

Example:

• Get number of previews of my Lunated theme and display it inline
  
• Get URL to screenshot file of my Lunated theme and display it inline
  

You can use media button to make the whole process a lot easier.

2. Formatted Output – return output based on format id

use attribute ‘format’

you can create and save a new format at plugin option page

Default format is : <a title="{name} has been previewed {hits} times" href="{demo}">Preview {name} ({hits})</a>

Example:

• Display using default format (you don’t have to specify the format id)
  
• Display using format id 1
  

You can use media button to make the whole process a lot easier.

3. Auto wrap output content with HTML paragraph <p> tag

use attribute ‘autop’

by default autop is set to true, which means it automatically wrap the output content with <p> tags

To display the content inline, use autop=”false”

Example:

We’ve detected ads as part of your theme. They need to be removed before your theme will be allowed into the theme directory.

I got this message above when I submit my Lunated theme to Wordpress Themes Directory. But the problem is, I do not have any advertisement or sponsored links in that theme.

I can’t seems to find the solution after some time. Therefore, I created a support thread and end up emailed the theme to wordpress team and told them the problem.

It’s Him. Hardcoded Google Adsense Codes

Finally, I got a reply from the team few hours later:

The upload process is picking up the hard coded adsense items in your theme (in header.php for instance). Generally when themes want to support showing ads like this they just provide a way to paste in the ad code.

So, in case you got the error message while you submit a theme, you know what to look for.

What did I mean by Hardcoded Google Adsense Codes?

It is actually the whole part of javascript provided by google adsense after you’ve created a new ads.

<script type="text/javascript">
<!--
google_ad_client = "pub-<?php echo $zenverse_global_adsense_id; ?>";
google_ad_width = 468;
google_ad_height = 60;
google_ad_format = "468x60_as";
google_ad_type = "text";
google_ad_channel = "";
google_color_border = "82cf1e";
google_color_bg = "82cf1e";
google_color_link = "555555";
google_color_text = "555555";
google_color_url = "555555";
google_ui_features = "rc:0";
//-->
</script>
<script type="text/javascript" src="http://pagead2.googlesyndication.com/pagead/show_ads.js"></script>

Now that I had this problem, what should I do?

All I wanted is to let save my theme users’ time, allow them to display google ads in a simple way – by just entering adsense publisher id.

Now that I had this problem, I can do nothing but to remove all adsense codes from the template files and provide a way to paste in the ad code in theme option page.

Last but not least, I’ve created a page for user to get adsense codes for their theme along with recommended background and text colours. Look, I want to save their time again

Things you also need to check

Beside google adsense, if you have advertisement slots (eg: 125×125 ads at sidebar) in your theme, you might get that message too. You don’t have to remove the slots, just disable them by default.

There are 2 functions available :

• wpeds_output()
• wpeds_return_data_as_array()

Function : wpeds_output()

Please read ” Using shortcode ” first to understand this page better.

Description

Allows you to output download stat in template files instead of using shortcode in post. It can accept argument in string or array and works exactly like the shortcode . Introduced in version 1.1

Usage

<?php 
if ( function_exists ( 'wpeds_output' ) ) {
wpeds_output($args);
}
?>

Parameters

url
(string) URL to the statistics page. Must be set.

format
(string) Format id. Default format will be used if you give an invalid format id.

get
(string) Get single info instead of using format.
Valid values : All available tags

autop
(string) Auto wrap the content with HTML paragraph <p> tag

• true – default
• false / 0 (to display content inline)

echo
(string) Show the result or keep it in a variable. Default is true.

• 1 (true) – default
• 0 (false)

Example of Usage

Display download stats using format id of 1

<?php 
if ( function_exists ( 'wpeds_output' ) ) {
wpeds_output( 'url=http://wordpress.org/extend/plugins/wordpress-theme-demo-bar/stats/&format=1' );
}
?>

Display number of download today (inline)

Wordpress Theme Demo Bar got <?php 
if ( function_exists ( 'wpeds_output' ) ) {
wpeds_output( 'url=http://wordpress.org/extend/plugins/wordpress-theme-demo-bar/stats/&get=today&autop=false' );
}
?> downloads today !!

Assign to variable

<?php 
if ( function_exists ( 'wpeds_output' ) ) {
$stored = wpeds_output( 'url=http://wordpress.org/extend/plugins/wordpress-theme-demo-bar/stats/&get=today&echo=0' );
echo $stored;
}
?>

Argument in array form

<?php 
if ( function_exists ( 'wpeds_output' ) ) {
$stored = wpeds_output( array( 
'url' => 'http://wordpress.org/extend/plugins/wordpress-theme-demo-bar/stats/',
'get' => 'today',
'echo' => '0',
) );
echo $stored;
}
?>

Function : wpeds_return_data_as_array()

Description

Allows you to get an array of saved data and assign it to a variable. It can accept argument in string or array. You can use this function to make a “download” page. Introduced in version 1.2.1

Usage

<?php 
if ( function_exists ( 'wpeds_return_data_as_array' ) ) {
wpeds_return_data_as_array($args);
}
?>

Parameters

url
(string) URL to the statistics page. If set, it returns an array of data of the selected item only. Use var_dump() to see what it has

gettype
(string) If set, it returns all datas of a type in array. Use var_dump() to see what it has
Valid values:

• plugin
• theme

autoformat
(string) By default, all time and number related data will be formatted based on plugin settings. Once disabled, timestamp will be returned for time-related data and unformatted numbers will be returned for number-related data.
Valid values:

• true – default
• false (false)
• 0 (false)

Example of Usage

Assign all plugins data into a variable

$stored = wpeds_return_data_as_array('gettype=plugin');
var_dump($stored); //to see what's inside

Assign all themes data into a variable

$stored = wpeds_return_data_as_array('gettype=theme');
var_dump($stored); //to see what's inside

Assign a single plugin’s data into a variable

$stored = wpeds_return_data_as_array('url=http://wordpress.org/extend/plugins/wordpress-extend-download-stat/stats/');
var_dump($stored); //to see what's inside

Disable auto-formatting all date and number

$stored = wpeds_return_data_as_array('gettype=theme&autoformat=0');
var_dump($stored); //to see what's inside

Argument in array form

$stored = wpeds_return_data_as_array( array(
'gettype' => 'theme',
'autoformat' => '0',
));
var_dump($stored); //to see what's inside

This is a part of The Complete Guide to Make your Own Wordpress Theme

Introduction

A basic wordpress theme should have a header, navigation menu, content, sidebar and footer. This is illustrated in the image below:

Header

Here lies your logo and usually, page or category navigation menu, and search box. It is also a common practive that google ads were placed here, so leave some space in the design to fit in the ads.

Content

You should make 2 seperate design for the content area:

• Latest posts at blog index. For each post, you can show its category, date posted, comment count and author name.
• Single post page with comments area (when you clicked into a post)

Sidebar

A sidebar should display important resources like category, recent posts, recent comment, blog roll and more. Some themes also put a search box at sidebar.

Footer

Here lies the copyright (eg: © 2009 zenverse , Powered by Wordpress) and link back to theme author.

Be creative

Of course, you do not have to follow this old style. What we have discussed above is a very basic & plain theme. You can be creative, change their position, add more features and make your theme special. We will discuss the features you can add to your theme later.

I am going to write a complete guide to create your very own wordpress theme along with features or functions you would need to improve the theme.

I’ve divided the guide into several parts. Currently it looks like this:

• What A Wordpress Theme Design Should Have
• Coding Your Wordpress Theme From PSD to XHTML
• Basic Wordpress Theme DIY : Introduction & Making of header.php
• Basic Wordpress Theme DIY : Making of index.php
• Basic Wordpress Theme DIY : Making of sidebar.php
• Basic Wordpress Theme DIY : Making of page.php and single.php
• Basic Wordpress Theme DIY : Making of comments.php
• Basic Wordpress Theme DIY : Making of footer.php
• Basic Wordpress Theme DIY : Making of search.php
• Basic Wordpress Theme DIY : Making of category.php
• Basic Wordpress Theme DIY : Making of archives.php & 404.php
• Advanced Wordpress Theme DIY : Widget-Ready Theme – Dynamic Sidebars
• Advanced Wordpress Theme DIY : Theme Options Page
• Advanced Wordpress Theme DIY : Adding Post Thumbnail to Blog Post
• Advanced Wordpress Theme DIY : Adding Related Posts and Popular Posts
• Advanced Wordpress Theme DIY : Twitter, Flickr , Feedburner and Google Adsense Integration
• Extra : Create a Fancy Search Box using CSS

I have completed 3 out of 17.

I will start working on the guide when I am free.

array(2) { ["errors"]=> array(1) { ["invalid_taxonomy"]=> array(1) { [0]=> string(16) "Invalid Taxonomy" } } ["error_data"]=> array(0) { } }

Now, I am pretty sure Wordpress 2.8.1 will be released very soon.

UPDATE : Wordpress 2.8.1 is already available, please upgrade now.

How to fix it?

- – - This temporary solution was removed because WP 2.8.1 is available now – - -

Side Notes

If you are using get_categories() to display category links in sidebar, you should really use wp_list_categories() instead.

Thank you for reading.