我正在开发一个简单的VoIP应用程序,但我很难理解它是如何工作的。这是我的AppDelegate.m
#import "AppDelegate.h"
#import "ViewController.h"
@implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
self.viewController = [[ViewController alloc] initWithNibName:@"ViewController_iPhone" bundle:nil];
} else {
self.viewController = [[ViewController alloc] initWithNibName:@"ViewController_iPad" bundle:nil];
}
self.window.rootViewController = self.viewController;
[self.window makeKeyAndVisible];
// Set-up scheduled background check-in.
[[UIApplication sharedApplication] setKeepAliveTimeout:600 handler:^{
//do your task
NSLog(@"startingKeepAliveTimeout");
}];
return YES;
}
- (void)applicationWillResignActive:(UIApplication *)application
{
}
- (void)applicationDidEnterBackground:(UIApplication *)application
{
// Set-up scheduled background check-in.
[[UIApplication sharedApplication] setKeepAliveTimeout:600 handler:^{
//do your task
NSLog(@"startingKeepAliveTimeout");
}];
}
- (void)applicationWillEnterForeground:(UIApplication *)application
{
[[UIApplication sharedApplication] clearKeepAliveTimeout];
NSLog(@"stoppingKeepAliveTimeout");
}
- (void)applicationDidBecomeActive:(UIApplication *)application
{
}
- (void)applicationWillTerminate:(UIApplication *)application
{
}
@end
我在模拟器和连接设备上看到的问题是,当我启动应用程序时,我会看到NSLog(@" stopsKeepAliveTimeout");从applicationWillEnterForeground:方法执行,但我从未见过NSLog(@" startingKeepAliveTimeout");应用程序最初启动时或从applicationDidEnterBackground执行时:
如何判断keepalive是否正在工作或甚至被调用?