Displaying a different theme for each day of the week_Drupal 6 Theming Cookbook-QQ阅读女频青春网

上QQ阅读APP看书，第一时间看更新

Displaying a different theme for each day of the week

This recipe provides the PHP code that allows the rotation of themes based on the day of the week.

Getting ready

As we have seen in other recipes in this chapter, a number of sites use an "odds and ends" module to handle tweaks and customizations particular to the site. We will be using the mysite.module created earlier in this chapter to hold our customizations. It is assumed that the module is available and already enabled.

How to do it...

Open the mysite module file and paste the following code into it:

/**
* Implementation of hook_init().
*/
function mysite_init() {
global $custom_theme;
// An array of themes for each day of the week.
// These themes do not have to be enabled.
$themes = array();
$themes[0] = 'garland';
$themes[1] = 'minnelli';
$themes[2] = 'bluemarine';
$themes[3] = 'pushbutton';
$themes[4] = 'chameleon';
$themes[5] = 'marvin';
$themes[6] = 'mytheme';
// Get the current day of the week in numerical form.
$day = date("w");
// Override current theme based on day of the week.
$custom_theme = $themes[$day];
}

Tip

If the module is named something else, the function mysite_init() will need to be renamed appropriately. In case the module already contains an existing hook_init() function, the contents of the function below will need to be integrated appropriately to the end of the existing function.

Save the file and then refresh the page on the Drupal site to see this snippet at work. Due to the nature of this feature, it might be necessary to fiddle with the computer's date settings to simulate different days of the week during testing.

How it works...

The function hook_init () is run on every page without exception. It is also run before Drupal gets to the theming stage when it displays every page. Consequently, this is the best place to override the theme to use.

We are overriding the site's theme by manipulating a global variable named $custom_theme. If it is set, then Drupal changes the theme being used to the value in this variable. Now that we know how to change the theme, it is just a question of when to do it. Since we are looking to change it based on the day of the week, we are going to take advantage of a feature of PHP's date() function which returns the day of the week as a number between zero and six.

// Get the current day of the week in numerical form.
$day = date("w");

We now map the $day variable to the $themes array which also has elements from 0 to 6 associated with seven enabled themes and, as a result, we obtain the equivalent theme for that day of the week. Finally, assigning our result to the $custom_theme variable overrides the default theme with the theme for the current day of the week.

There's more...

The PHP code used in this recipe can be easily modified to display a random theme on every page load.

Displaying a random theme

Instead of displaying a preset theme for each day of the week, integrating the following snippet into the mysite_init() function will display a random theme on every page load:

// Override current theme randomly.
$custom_theme = $themes[array_rand($themes)];