QResizeObserver is a Quasar component that emits a resize event whenever the wrapping DOM element / component (defined as direct parent of QResizeObserver) changes its size (width and/or height). The reported size is the element’s outer size (padding and border included), so a padding change on the wrapping element itself is reported too. Note that no polling is involved, but overusing it is costly too.
Should you prefer the size as reactive state in your setup code, or want to watch an element that is not the direct parent, use the useElementSize composable that this component is built on. The v-resize directive is the template-side alternative that needs no extra node.
Usage
Please note that QResizeObserver will issue an event as soon as it gets rendered and attached to DOM, so you can have the initial size of the container.
Accessibility v2.25+
QResizeObserver renders nothing, so it has no accessibility surface.