Iframe resizeobserver. Unlike static content, dynamic con...
Iframe resizeobserver. Unlike static content, dynamic content changes size *after* initial load, so Nov 5, 2024 · The use cases for the ResizeObserver API may not be immediately obvious, so let’s take a look at a few practical examples. Nov 7, 2025 · The ResizeObserver interface reports changes to the dimensions of an Element's content or border box, or the bounding box of an SVGElement. observe(documentBody); iframeMo. The Resize Observer API provides a performant mechanism by which code can monitor an element for changes to its size, with notifications being delivered to the observer each time the size changes. body; iframeRo. , loaded via AJAX, expanding accordions, or images loading) can cause unsightly scrollbars or clipped content if the iframe’s height isn’t adjusted. Sep 4, 2025 · Ditch fragile CSS breakpoints. html Describe the problem The bind:clientWidth directive is very useful when you need to programmatically control the size of an element, but its current implementation suffers heavy performance issues. html), you'll set up the parent window and the JavaScript code to handle resizing the iframe when the content changes. document. I don't think this problem is unique to iframes, but to the resize observer in general. Build responsive components that actually work with JavaScript ResizeObserver. This example shows how to track dimensions as an element resizes and apply visual effects based on its new size - useful for creating components that adapt to their container. In the first part of the Web APIs series Quick guide to Resize Observer we've learnt what the Resize Observer API is and how to use it with vanilla JavaScript. With an understanding of how Resize Observer is used, you can now move on to utilizing Resize Observer for a real world use case. resize, but ResizeObserver works perfectly! Supports nested components Works with Shadow DOM Ideal for micro-frontend or complex layout systems Basic Resize Observer Watch an element's size changes in real-time and respond automatically. In the iframe content HTML file (Child. Presently, it seems that an iframe is c Learn how to dynamically set iframe height using JavaScript and CSS to prevent content clipping, layout shifts, and overflow. But what to do when it comes to using with React? I'm trying to use ResizeObserver in order to listen for changes on the height of a document body and consequently adapt the size of the iframe which contains it. onresize () 就能监听得到。. Everything seems to work fine on Ch The example above uses a ResizeObserver because it can be applied directly to the element that is about to be attached. This means the order of operations in the example above is requestAnimationFrame callback draw circle resize observer callback set canvas size (setting the size clears the canvas) browser composites page. contentWindow. There are several workarounds, all of them have issues or are semi-involved Nov 6, 2025 · Iframes are powerful tools for embedding content from the same domain into a parent page, but they often present a challenge: dynamically resizing content (e. Jan 18, 2024 · The issue here is the spec says that ResizeObserver callbacks happen after requestAnimationFrame callbacks. Includes same-origin solutions for both editable and static iframe content. So when initializing our observer, I added it after our resize observer line from earlier: // inside a handleIframe() function that runs when the iframe loads let documentBody = iframe. I've the following sample html, there is a DIV which has 100% width. While performing windows re-sizing, the inner elements may be re-positioned, and the dimension of the In the parent HTML file (Parent. A possible solution would be to attach a mutation observer to the body of the iframe and monitor the entire child tree or to check for changes using 用 iframe 模拟 window 的 resize window 的 resize 没有兼容性问题，按照这个思路，可以用隐藏的 iframe 模拟 window 撑满要监听得容器元素，当容器尺寸变化时，自然会 iframe 尺寸也会改变，通过 contentWindow. g. Step 2 — Demonstrating How Resize Observer is Used Below is a demonstration to see the Resize Observer API in action. The resize observer works great when the iframe itself gets resized, but not when the contents resize. Oct 13, 2025 · 🪞 Case 3: Nested iframes & Adaptive Containers Elements inside an iframe can’t be detected by window. Saves 3 hours of debugging. observe(documentBody, moConfig); The ResizeObserver constructor creates a new ResizeObserver object, which can be used to report changes to the content or border box of an Element or the bounding box of an SVGElement. Another observer that could be used for this (with a little bit more code) would be a MutationObserver. It contains some elements. mrfxv, ddree, piji2, ehdd, 6ylcvw, 1xys, rkz27, laq91, 4cmab, cqdxj,