Boom. When the panel with the Flash is rendered, it takes over the entire page. Not quite what I want it to do.

So I see the Flash is being created in js code, using something called AC_FL_RunContent(). It’s from the Adobe Flash Player Detection Kit - a handy javascript library that will render cross-browser html to show your movie. Using…document.write! Yow!

So a bit of googling turns up only a few forum posts discussing how to render Flash inside of Ext components. One popular solution is to use the uxmedia Ext extension…but it’s not open source for commercial use. And in addition, I don’t need a pretty way to invoke my Flash, I just need the existing Web 1.0 way to just work inside an Ext component.

So, time for a little hackery. The Flash Player Detection Kit includes the helpful file AC_OETags.js, which is what you would include with your webapp. You call the javascript function AC_FL_RunContent(), passing a bunch of arguments. So here’s the simple hack: instead of document.write-ing the string, change the code to return that string to you. Make AC_Generateobj return the str, and make AC_FL_RunContent return the results.

Now in your client code, capture the html:

var flash_object_markup = AC_FL_RunContent(.......);

And then render it into a div using a Panel.

// assuming <div id="flash_content"></div>
var content = new Ext.Panel({
  html: flash_object_markup
});
content.render('flash_content');

And now the flash object is contained and manged by ExtJS.

I’m sure hacking the Adobe js file isn’t for everyone, but I think it’s perfectly reasonable. And if you have pre-existing js code that creates Flash html with the Detection Kit, this is a pretty seamless way to get them integrated with ExtJS. And nobody should be using document.write, anyway.

<code>svn revert file.rb</code>

In git, you don’t add that file to your staging area for commit. To make your changes go away forever, you checkout a new copy of that file from HEAD.

<code>git checkout — file.rb</code>

If you omit the –, it will still work, as long as you don’t have a branch named the same as your file. Thanks to Jonathan Dance at norbauer.com - one of the few blog entries I found describing this technique.

2009-04-28 UPDATE - err has a great git cheatsheet that includes this trick under Fixing Mistakes.

This means the url in the browser location bar will NOT end with “.csv”. Don’t do this on Rails 2.2.2 and earlier!

Rails 2.2.2 properly sets the Content-Type to text/csv. But that’s not enough for our browser to know what to do with it. Poking around this morning reveals that Numbers on my MacBook Pro will not open the csv file without an extension. Same issue reported by QA on Windows with IE and Firefox and Microsoft Excel. Same results whether you let the browser open the file in an app directly, or Save As and then open it.

Along with the content-type, the filename and extension needs to be correct.

I fixed this on the server side, by forcing a disposition header the same way send_data does.

respond_to do |format|
  format.html
  format.csv { headers["Content-Disposition"] ||= "attachment; filename=\"#{params[:action] + '.csv'}\"" }
end

Now we get a disposition header, which explicitly tells the browser what type of file it is.

Content-Disposition: attachment; filename="index.csv"

This is ugly. Don’t do it. It won’t be needed when this patch, which removes the formatted_ routes, it released. It seamlessly keeps support for incoming requests such as “/posts.csv” working as they should.

So the moral of the story is: don’t be overzealous and stop using formatted routes yet! When you upgrade your app, just remove the formatted routes from routes.rb and everything will continue to work as it should.

controller.use_rails_error_handling!

But since none of us wants to have to add this to each of our controller specs, add this to your configure block in spec_helper:

Spec::Runner.configure do |config|
  config.before(:each, :type=>:controller) {controller.use_rails_error_handling!}
end

I was mising :source => :group from my association. Perfect message. The code knew what was missing, and it told me in a way that could be literally copied and pasted. Do write code like this when you can.