We’ve known for some time that simply assigning to window.onload is bad. Simon Willison created addLoadEvent a long time back to work around the problem. But I’m in Rails, and we have prototype. So what’s the correct idiom?
Well, after a bit of playing, it seems to be this:
<% content_for("page_scripts") do %>
Event.observe(window, 'load',
function() { $('username').focus() }
);
<% end %>
I do love that $() function.
This assumes that you have a layout that looks something like this, in order to insert bits of JavaScript into the head.
<script type="text/javascript">
<%= @content_for_page_scripts %>
</script>
Anyway, the solution seems a little more verbose than addLoadEvent(), but not disastrously so.
Jabbering Giraffe 