title: How does one React component call a method in another React component?
body: <p>My page contains two completely separate React components (different files, different classes, no parent-child relationship).</p>
  
  <p>How can one component call an instance method in another component? The problem seems to be obtaining the instance of the target component.</p>
  
  <p>EDIT: Both components share the same parent (i.e. they are rendered in the same <code>render()</code> method) but I still don't know how to pass the reference of the target component to the calling component.</p>