Head over to the WordPress plugin repository to download it (and rate it)!

The widget control panel

ColorBoxes admin view

ColorBoxes is my latest WordPress plugin, allowing users to easily insert alert-style messages (just like the one above) at the top of any page or post. Just like SimpleMap, this plugin was born out of a need on a client’s website. I needed a foolproof way for these alerts to be made without going into the HTML editor and making <div> tags with custom classes.

It works by setting post meta values, just like a Custom Field would. It’s lightweight, fast, and easy-to-use. Go ahead and download it here!

1. Use the $wpdb object for all database queries

If you only read and follow one of these tips, make it this one. Setting up database connections with mysql_connect over and over again is a waste of code. If you’re in anything other than a standalone processing script, $wpdb is ready to go with just one line of code:

global $wpdb;

(If you are using a standalone script for something, just include two files to make $wpdb work: wp-load.php and wp-includes/wp-db.php.)

There are different functions for the $wpdb class to make different kinds of database queries (see the WordPress codex page for details on them all).

On average, I find that using $wpdb saves two to three lines of code for each time I make any sort of database query. For example, this:

$name = mysql_real_escape_string($name);
$result = mysql_query("INSERT INTO $myplugin->categories_table (name) VALUES ('$name')");
if (!$result)
    die("Could not insert into database. ".mysql_error());

turns into this:

$wpdb->insert($myplugin->categories_table, array('name' => $name), array('%s'));

One of the most important reasons to use $wpdb instead of mysql_query is that it automatically protects the database from MySQL injection attacks. More details about that are on the codex page as well.

2. Call jQuery using wp_enqueue_script

One of the most frustrating things I’ve seen responsible for my WordPress plugins not working is that other plugins are calling jQuery the wrong way:

<script src="../../../wp-includes/js/jquery/jquery.js" type="text/javascript"></script>

WordPress has its own way of handling calls to jQuery (and other common Javascript libraries). It’s called wp_enqueue_script. This is how WordPress would have you call jQuery in a plugin:

wp_enqueue_script('jquery');

So if WordPress itself needs to load jQuery, or an additional plugin calls it in this way, then it’s only loaded once, and it’s loaded in no-conflict mode. This means that there won’t be two jQuery scripts of different versions competing for attention. And if you prefer an external reference to jQuery (such as the one from Google Code), there is a method for doing that in a WordPress-friendly way, too (see step 2 on this linked page).

3. Use unique class & function names

If you have a function in your plugin called “load()”, then what happens if another plugin is activated on a user’s blog that uses a function called “load()”? Well, crap explosions happen. Plugins break. Solving this problem is easy: name all your functions something unique to your plugin. My personal method is to come up with a two- or three-letter representation of my plugin (like “sm” for SimpleMap) and use that as a prefix to all my function names. For example:

sm_display_map()

Easy as pie.

4. Prep all text for localization from the get-go

Even if you don’t include any translation files with your plugin, someone out there might want to write one for you (or for themselves). It’s pretty tedious to go back through your existing code and prep the text for translation, so make it a habit right away. First, you have to pick a key for your plugin’s translation files (this is usually just the plugin name or slug). Then you have to surround any text that gets displayed to the user with the following code:

__('This is the text to be translated.', 'PluginKeyHere');

Note: ‘PluginKeyHere’ would be the key you picked. For example, in SimpleMap this is ‘SimpleMap’.

The double underscore at the beginning will return the translated string to PHP. If you want to echo the string, instead of adding echo before the double underscore, you can use this shorthand:

_e('This is the text to be translated.', 'PluginKeyHere');

More details on localizing your plugin can be found in the WordPress codex.

5. Write a good README file

This is something I highly recommend. When I’m searching for a plugin to install, an inadequate or poorly written README file will often make me go back to my search results and keep looking. Writing a good README file shows that you care about the people using your plugin. If you treat it like it’s just a step WordPress forces you to take to submit a plugin to the repository, it’s going to make you look like an ass, and users won’t want to try your plugin at all.

To top it off, Mark Jaquith has recently released a plugin that makes good use of your README files on your own blog. It’s called I Make Plugins, and it automatically populates pages on your blog to promote the plugins you’ve created. You can see it in action here on Aliso the Geek.

Well, that’s all for now. More tips are sure to come in the future! If you have any suggestions, please leave a comment and share them!

• The bug preventing the database from being created is FIXED.
• The Search function correctly searches Name, Description and Tags (but not Category yet).
• You can now choose an address format for the “city” line. There are seven different format options.
• The page now scrolls up to the map when you click on a result in the list.
• Changing a location’s address in Quick Edit forces you to re-geocode before saving the changes.
• “No Results Found” is now a translatable string.
• A location’s phone number now has a “Phone:” label in the info bubble as well as the results list.

A huge thanks to all my beta testers and translators. I’ve been keeping the translation files updated with each beta release, so please send me your .po files once you’ve translated them.

For the benefit of anyone using the beta, here are the bugs I’m aware of:

• Tables aren’t created on install (this is a BIG one; it’s first on my list to fix)
• Distance conversion/calculation error—differs from Google’s distance estimate when kilometers are used
• Search for keywords not working properly (FULLTEXT error)
• “No Results Found” is not being translated
• Need to add options for the display order of address elements (i.e. putting postal code ahead of city for certain countries)

I’m hoping to pound through all of these this weekend, so we’ll see how it goes.

Please check out the Beta Testing Forum if you want to participate.

[simplemap]

If you want to show only specific categories, you just need to do this:

[simplemap categories=4,12]

…where 4 and 12 are the ID numbers of the categories you want to show. The ID number of a category is automatically generated and will be shown in the Manage Categories screen for easy reference.

Also, categories are just better in general now; if you change a category’s name, it will update it in all the affected locations. It’s not perfect yet, but it’s much better than it used to be.

Tags are done, as is the ability to search them. The search now looks in the name, description, category, AND tags.

I found a great CSV processing class that should improve that functionality tenfold. Hopefully my beta testers will help confirm this!

In order to get these changes out there, I’m not going to include custom map markers in 1.2. They are next on the list and will come in 1.2.1. I’m really pushing myself on this and I’m hoping to get the beta out in the next day or two. Keep in mind that the beta should NOT be used in a production environment, because there’s no guarantee that it’s free of bugs and defects.

SimpleMap Support Forums are now live! Click on the “Forum” link in the header to get to them. You can post in the forums without having to register, but you will have to provide your name and email address. I will leave the comments open on the SimpleMap page for now, but I strongly encourage anyone with a support-type question to post in the forums. This is my first time hosting or administering a forum, so please bear with me as I learn the ropes!

A huge thanks to Simple:Press Forum for making this possible. The plugin is so easy to use! It even gave me a couple of ideas for improving SimpleMap’s usability.

In light of this, I am working on a support forum for SimpleMap. I’m using the awesome Simple:Press forum plugin for it. I’m extremely impressed with Simple:Press so far—I’ve seen my husband set up other forums in the past, and this install was so much easier than any of those. The level of control and customization blows me away, especially for a completely free plugin!

That little donation module in the top-right corner of the Simple:Press site is a pretty great idea. I might be adding something similar soon… we’ll see.

That being said, I’m nearing a point with SimpleMap where my work on it will be a little more sporadic for a while. I’ve been working on it almost every night, and as I get closer to being done with 1.1.4 (and closer to starting 1.2) I feel that soon, there will only be bug fixes to worry about for a while. After 1.2 I don’t plan on adding any more major features. 1.2 will definitely bring more functionality to the location categories, including the ability to assign custom map markers for each category and to hide/show certain categories on your map.

In the relatively near future, I’m considering either opening up SimpleMap’s issue tracker to the public, or adding a support forum, so that there’s a more organized way of keeping questions, answers, bugs, and fixes online. I may not be developing new features for SimpleMap after 1.2 (at least not for a while), but I will still provide support as best I can.

The reason I’m thinking so seriously about this is because I’m starting another project. It’s something big, something involving WordPress that’s bigger than just a plugin. I am hoping to have it done by January 2010, or at least in beta by then. It will be a paid service, and it has a very specific target audience in mind, so a lot of the people using SimpleMap might not necessarily be interested in it. Anyway, it’s huge, it’s exciting, and it needs my time and attention if it’s ever going to get done. I’m working with my husband on it, and it will ultimately be a Barrett Creative product.

I don’t want to give much more away, so that’s it for now. Rest assured that you will see sneak peeks of the new project every now and then… and I will still be here for any and all SimpleMap questions. I do plan on concentrating on it as much as I have been until 1.2 is released. 1.1.4 is close enough to done that it should come out this week.