Calling a script file before video plays in Roku

I came across a question in stackoverflow : http://stackoverflow.com/questions/20958093/roku-using-urltransfer-to-call-script-file/21725120#21725120 , where one of the user wanted to execute a script before the video actually starts playing. You should be able to see more details of the problem in the above mentioned link too.
The solution to this is to make HTTP call using roUrlTransfer object just before you call play function for roVideoPlayer, or if you are using roVideoScreen then just before the show function of roVideoScreen.  A pseudo code is as follows:

For roVideoPlayer

player=CreateObject('roVideoPlayer')
* Your code to add content for the player
* Your call to script
player.play()

For roVideoScreen

player=CreateObject('roVideoScreen')
* Your code to add content for the player
* Your call to script
player.show()