show Confirm Perspective Switch dialog box

[mostafa]

Hi.
I am writing a plug-in for eclipse for working with some kind of file types.
I would like to show a "confirm dialog box" to the users when they open a specific file type that my plug-in support,
to ask them for switching to my plug-in perspective (view).
just like the time you want to debug your program, and eclipse bring a dialog box which
says: "Confirm Perspective Switch" in the heading and "! This kind of launch is configured to open
the Debug perspective when it suspends. This Debug perspective is designed to support application debugging... .Do you want to open this perspective now?"

how can I do this. In fact is there any item in configuration for doing this work? if No , how can I do this with writing code?
for the first I know that I should show a dialog to the user for changing the perspective. if the user clicked the yes button I should call a function that I don't know the exactly name of it to change perspective.