KSDIdlingWindow.h

//
//  KSDIdlingWindow.h
//
//  Created by Brian King on 4/13/10.
//  Copyright 2010 King Software Designs. All rights reserved.
//
// Based off: 
//  http://stackoverflow.com/questions/273450/iphone-detecting-user-inactivity-idle-time-since-last-screen-touch
//

#import <UIKit/UIKit.h>

extern NSString * const KSDIdlingWindowIdleNotification;
extern NSString * const KSDIdlingWindowActiveNotification;

@interface KSDIdlingWindow : UIWindow {
	NSTimer *idleTimer;
	NSTimeInterval idleTimeInterval;
}

@property (assign) NSTimeInterval idleTimeInterval;

@property (nonatomic, retain) NSTimer *idleTimer;

@end

KSDIdlingWindow.m

//
//  KSDIdlingWindow.m
//
//  Created by Brian King on 4/13/10.
//  Copyright 2010 King Software Designs. All rights reserved.
//
// Based off: 
//  http://stackoverflow.com/questions/273450/iphone-detecting-user-inactivity-idle-time-since-last-screen-touch
//

#import "KSDIdlingWindow.h"

NSString * const KSDIdlingWindowIdleNotification   = @"KSDIdlingWindowIdleNotification";
NSString * const KSDIdlingWindowActiveNotification = @"KSDIdlingWindowActiveNotification";

@interface KSDIdlingWindow (PrivateMethods)
- (void)windowIdleNotification;
- (void)windowActiveNotification;


@end


@implementation KSDIdlingWindow
@synthesize idleTimer, idleTimeInterval;

- (id) initWithFrame:(CGRect)frame {
	self = [super initWithFrame:frame];
	if (self) {
		self.idleTimeInterval = 0;
	}
	return self;
}
#pragma mark activity timer

- (void)sendEvent:(UIEvent *)event {
    [super sendEvent:event];
	
    NSSet *allTouches = [event allTouches];
    if ([allTouches count] > 0) {

		// To reduce timer resets only reset the timer on a Began or Ended touch.
        UITouchPhase phase = ((UITouch *)[allTouches anyObject]).phase;
		if (phase == UITouchPhaseBegan || phase == UITouchPhaseEnded) {
			if (!idleTimer) {
				[self windowActiveNotification];
			} else {
				[idleTimer invalidate];
			}
			if (idleTimeInterval != 0) {
				self.idleTimer = [NSTimer scheduledTimerWithTimeInterval:idleTimeInterval 
																  target:self 
																selector:@selector(windowIdleNotification) 
																userInfo:nil repeats:NO];
			}
		}
	}
}


- (void)windowIdleNotification {
	NSNotificationCenter *dnc = [NSNotificationCenter defaultCenter];
	[dnc postNotificationName:KSDIdlingWindowIdleNotification 
					   object:self
					 userInfo:nil];
	self.idleTimer = nil;
}

- (void)windowActiveNotification {
	NSNotificationCenter *dnc = [NSNotificationCenter defaultCenter];
	[dnc postNotificationName:KSDIdlingWindowActiveNotification 
					   object:self
					 userInfo:nil];
}

- (void)dealloc {
	if (self.idleTimer) {
		[self.idleTimer invalidate];
		self.idleTimer = nil;
	}
    [super dealloc];
}


@end

Thanks for the code snippet - definitely made it easy to see where I needed to start.

Thanks for the snippet - very helpful!

But how can we use it further? I have set my rootviewcontrollers to this customwindow object. But it doesn't give any results?

How to use this snippets in particular view controller, in Swift 3?

In the app delegate add the following:

{
    static KSDIdlingWindow *customWindow = nil;
    if (!customWindow) customWindow = [[KSDIdlingWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    return customWindow;
}