ventana

Window event microlibrary. Exposes a pretty API for window events and utilities.

ventana.on('scroll', function() {
  console.log('User scrolled');
});

Usage

Ventana is available as a standard npm module. Additionally, you can use the minified UMD file.

API

ventana.on(Object target, Function callback)

Bind to window events:

• move - Triggered when the user scrolls on either axis.
• resize
• destroy (close tab or entire window)
• hide (move to another tab)
• show

move and resize callbacks receive an object parameter with timestamp, scrollTop, scrollLeft, width, and height.

Performance note

For performance reasons, the move event (aka scroll) is implemented via requestAnimationFrame.

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ventana.queue(Function callback)

Queue up a function to be called after the next requestAnimationFrame loop completes.

Primitive Abstractions

Under the hood, there are two main abstractions used to implement Ventana: streams and queues.

Streams

The Ventana stream is a simple abstraction around lists of listeners with the ability to filter on values and work nicely with queues. Listeners can be functions, other streams, or queues. You write a single value to the stream, and each listener gets called with that value. Streams are used to represent a single type of repeatable event, like the user scrolling or the window being re-sized. In the later case, the value being passed by the stream could be the updated dimensions of the window.

Queues

Ventana queues represent a set of objects that can receive a stream of values, i.e. a Stream. Queues are usually an abstraction above a paired stream. For instance, a queue can represent a list of DOM objects that need to be modified when the user scrolls. In this example, a stream representing scroll events could be piped into the queue representing the DOM objects.