title: Callback when DOM is loaded in react.js
body: <p>I want to have a callback invoked on my react.js component when its DOM element (including all child nodes) is actually loaded on the page and ready. Specifically, I have two components that I want to render the same size, choosing the maximum of whichever component has the larger natural size.</p>
  <p>It looks like <code>componentDidMount</code> is not really what I want because it is only called once per component, but I want my callback to be called again anytime the component is finished rendering. I thought I could add an <code>onLoad</code> event to the top level DOM element, but I guess that only applies for certain elements, like <code>&lt;body&gt;</code> and <code>&lt;img&gt;</code>.</p>