I am working on an app with passcode locking option(pic1). When I enter correct password it enters into the app.When I enter wrong password it will perform some other action(pic2).

After some time the app goes into the sleep state,when the app comes to active state we have to enter the password again.
Here my requirement is I want to open the “passcode locking screen” (pic1.,which was created by me) after unlocking the device,(pic3.,which is default locking option in Iphone). Unless I enter the correct passcode the “passcode screen” should stick to the window. It should not move to any other screen (pic4., screen with group of app icons) though I click the button of theiphone.
This requirement is killing my time, I don’t mind to post sample code or tutorials if you have gone through.
you can’t do this using a non-jailbreak iPhone. an app cannot prohibit the user from switching to another app (and it cannot modify another app)
that applies to the springboard (pic4) too of course