Riot.js

Riot.js tags can use access DOM elements of the HTML inside the tag if the DOM elements have a ref attribute. Here is an example Riot.js tag definition which declares an <input> element with ref attribute, and a JavaScript that accesses that <input> element:

<mytag>
<h1>The Title</h1>

<form>
<input ref="abc" type="text" value="123"/>
<input type="submit" value="Click" />
</form>

<script>
this.on("mount", function() {
	console.log("on mount");
	console.log(this.refs.abc.value);	
})	
</script>
</mytag>

Notice the this.on("mount", ...) function call in the JavaScript block. This function call adds a "mount" event listener function which is fired when the tag is mounted in Riot.js.

Inside the function passed to the this.on("mount", ...) function call you can access the DOM elements with the ref attributes. You do so via the this.refs object. In the example above this is done via the statement this.refs.abc.value . This statement reads the value of the DOM element with the ref attribute abc.

The this.refs object is not populated until the "mount" event has been fired. That is why the example accesses it inside a "mount" event listener. This is important to keep in mind, as accessing the this.refs object at any time before the "mount" event has fired would leave you with an empty this.refs object - making access to the DOM elements impossible.