--- title: Pattern.on() --- The `Pattern.on()` method allows you to attach a function to one of the pattern's [lifecycle hooks](/reference/hooks/). It takes the lifecycle hook's name as the first argument and the function as the second. This method will then be triggered by the lifecycle hook. :::noteThis method is chainable as it returns the Pattern object::: ## Pattern.on() signature ```js Pattern pattern.on(string hook, function method) ``` :::tip Refer to [the Lifecycle hooks documentation](/reference/hooks/) for a list of all available lifecycle hooks, as well as the signature of the function you should pass it. ::: ## Pattern.on() example ```js pattern.on('preRender', function(svg) { svg.style += "svg { background: yellow;}"; }) ``` Your pattern now has a yellow background. :::tip The [plugin guide](/guides/plugins/) contains more info on how you can use hooks :::