In this tutorial I'll show how you can programmatically and dynamically remove a column from your view. In my example, I chose to hide an email column from unauthenticated users, but you could apply this code to do pretty much anything.

To get things started, I defined a content type of "Profile" to contain some user details (using the Content Profile module) and used the Devel module's generate users and nodes functionality to create some sample data. I then created a view to show the data:

Here is my page view display:

Now you can add the hook_views_pre_build() function in your module. Since the $view object is large, I recommend using krumo() (which comes with the Devel module) to browse through the $view object's properties.

The above code will neatly format the $view object in a hierarchical display. You can click to expand each class property.

As you can see, the $view object has a lot of data in it. At this point, you'll need to get acquainted with the structure of the handler object of the view ($view->display['default']->handler) and determine what to modify. To remove the email column for unauthenticated users, you can add the following code:

When I logout, my view no longer shows the email column:

I recently created a view to show all the nodes that exist in a user's organic groups. I originally created the same view in Drupal 5 by adding the filter "OG: Post in User Subbed Groups" is equal to "Currently Logged In User". Unfortunately, I could not find the equivalent filter in Drupal 6 Views, so I decided to use arguments. Argument handling code is structured a differently in Drupal 6:

1) add a new argument
2) for "Action to take if argument is not present" choose "Provide default argument"
3) for "Default argument type" choose "PHP Code"
4) for "PHP argument code" I entered:

It's a personal preference of mine to NOT insert code into my database, so I added the previously called function into a module. IMHO, code belongs in subversion so it can be versioned properly, not in a database. Here's my function definition: