In Grails: A Quick-Start Guide, we have a task list to help TekEvent organizers and volunteers keep track of what's left to be done for their event. It's pretty handy, but it could be a bit easier to use. Specifically, it would be great if we didn't have to click on a task to open the show view and then click again to edit it, just to mark a task as completed. What would be really nifty is if we could mark a task as completed by clicking on a simple checkbox. And it turns out that Grails provides an Ajax tag that's just what we need.

Closures are reusable code blocks in Groovy. The code of the closure is executed against the delegate of the closure. By default the owner of the closure is the same as the delegate, but we can change this. We can define which object is the delegate for a closure, so we can change the object the closure is executed for.

Spring Security is one of the basic building blocks I use pretty much every time I'm constructing a web application. It's a very mature and incredibly powerful security framework, one of its main benefits being its versatility. There are hooks and plugs everywhere, allowing you to extend and combine basically any way you want. Now, if you want to apply security in a Grails application you are typically pointed in the direction of the Grails Acegi Plugin, which does a rather decent job at applying basic security to your Grails application. It quickly falls short ...