Auto Lock iPhone programmatically

I am working on an alarm app, which needs to auto-lock the device after a particular time period, since most of the clock applications in 开发者_StackOverflow中文版the App Store have that feature.

If you would like to lock the phone after 5 minutes then do the following:
set this: [[UIApplication sharedApplication] setIdleTimerDisabled:YES];
and also set a timer: [NSTimer scheduledTimerWithTimeInterval:240 target:self selector:@selector(disableIdleTimer) userInfo:nil repeats:NO];
And in the disableIdleTimer method you will set this: [[UIApplication sharedApplication] setIdleTimerDisabled:NO];

This will work with the following condition: the iPhone's autolock function is set to the minimum (1 minute).

As I see in the moment, there is no better method.