This modifier triggers a callback when resize events are observed on the target element.

Basic Usage

A callback handler is always expected to be passed to did-resize:

  <div {{did-resize this.onResize}}></div>

The handler will be called with an instance of ResizeObserverEntry and the ResizeObserver instance itself:

  onResize(entry, observer) {
    // do something

Here is an example of using the did-resize modifier to increment a counter every time the containing <div> has been resized:

I have been resized 0 times!
<div {{did-resize this.onResize}}>I have been resized {{this.count}} times!</div>

Advanced Usage

did-resize also supports passing an options hash into ResizeObserver:

  <div {{did-resize this.onResize this.options}}></div>

The options supported are documented under ResizeObserver.observe.