将以下两个文件添加到您的项目中(original source here) :
ELCUIApplication.h
//
// ELCUIApplication.h
//
// Created by Brandon Trebitowski on 9/19/11.
// Copyright 2011 ELC Technologies. All rights reserved.
//
#import <Foundation/Foundation.h>
// # of minutes before application times out
#define kApplicationTimeoutInMinutes 2
// Notification that gets sent when the timeout occurs
#define kApplicationDidTimeoutNotification @"ApplicationDidTimeout"
/**
* This is a subclass of UIApplication with the sendEvent: method
* overridden in order to catch all touch events.
*/
@interface ELCUIApplication : UIApplication {
NSTimer *_idleTimer;
}
/**
* Resets the idle timer to its initial state. This method gets called
* every time there is a touch on the screen. It should also be called
* when the user correctly enters their pin to access the application.
*/
- (void)resetIdleTimer;
@end
ELCUIApplication.m
//
// ELCUIApplication.m
//
// Created by Brandon Trebitowski on 9/19/11.
// Copyright 2011 ELC Technologies. All rights reserved.
//
#import "ELCUIApplication.h"
@implementation ELCUIApplication
- (void)sendEvent
UIEvent *)event {
[super sendEvent:event];
// Fire up the timer upon first event
if(!_idleTimer) {
[self resetIdleTimer];
}
// Check to see if there was a touch event
NSSet *allTouches = [event allTouches];
if ([allTouches count] > 0) {
UITouchPhase phase = ((UITouch *)[allTouches anyObject]).phase;
if (phase == UITouchPhaseBegan) {
[self resetIdleTimer];
}
}
}
- (void)resetIdleTimer {
if (_idleTimer) {
[_idleTimer invalidate];
// [_idleTimer release];
}
// Schedule a timer to fire in kApplicationTimeoutInMinutes * 60
float timeout = kApplicationTimeoutInMinutes * 60;
_idleTimer = [NSTimer scheduledTimerWithTimeInterval:timeout
target:self
selector
selector(idleTimerExceeded)
userInfo:nil
repeats:NO];
}
- (void)idleTimerExceeded {
/* Post a notification so anyone who subscribes to it can be notified when
* the application times out */
[[NSNotificationCenter defaultCenter]
postNotificationName:kApplicationDidTimeoutNotification object:nil];
}
//- (void) dealloc {
// [_idleTimer release];
// [super dealloc];
//}
@end
在您的 Supporting Files 文件夹中打开 main.m，更新以下内容:
#import <UIKit/UIKit.h>
#import "AppDelegate.h"
int main(int argc, char *argv[])
{
@autoreleasepool {
return UIApplicationMain(argc, argv, @"ELCUIApplication", NSStringFromClass([AppDelegate class]));
}
}
在 AppDelegate.m 中编辑 didFinishLaunchingWithOptions: 方法并添加 applicationDidTimeout: 方法。
- (BOOL)applicationUIApplication *)application didFinishLaunchingWithOptionsNSDictionary *)launchOptions
{
// Override point for customization after application launch.
[UIApplication sharedApplication].idleTimerDisabled = YES;
[[NSNotificationCenter defaultCenter] addObserver:self selectorselector(applicationDidTimeout
name:kApplicationDidTimeoutNotification object:nil];
return YES;
}
- (void) applicationDidTimeoutNSNotification *) notif {
NSLog(@"applicationDidTimeout");
[UIApplication sharedApplication].idleTimerDisabled = NO;
}