object c AppDelegate.h 各个方法的使用

//
//  AppDelegate.m
//  
//
//  Created by Kenshin Cui on 14-2-23.
//  Copyright (c) 2014年 Kenshin Cui. All rights reserved.
//

#import "AppDelegate.h"

@implementation AppDelegate


//程序启动之后执行，只有在第一次程序启动后才执行，以后不再执行；
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    return YES;
}


// Sent when the application is about to move from active to inactive state. 
// This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) 
// or when the user quits the application and it begins the transition to the background state.
// Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. 
// Games should use this method to pause the game.
//程序将要被激活时（获得焦点）执行，程序激活用户才能操作；
- (void)applicationWillResignActive:(UIApplication *)application
{
  
}

// Use this method to release shared resources, save user data, invalidate timers, 
// and store enough application state information to restore your application to its current state in case it is terminated later. 
// If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
//程序进入后台后执行，注意进入后台时会先失去焦点再进入后台；
- (void)applicationDidEnterBackground:(UIApplication *)application
{
    
}

// Called as part of the transition from the background to the inactive state; 
// here you can undo many of the changes made on entering the background.
//程序将要进入前台时执行；
- (void)applicationWillEnterForeground:(UIApplication *)application
{
    
}

// Restart any tasks that were paused (or not yet started) while the application was inactive. 
// If the application was previously in the background, optionally refresh the user interface.
//程序被激活（获得焦点）后执行，注意程序被激活时会先进入前台再被激活；
- (void)applicationDidBecomeActive:(UIApplication *)application
{
    
}

// Called when the application is about to terminate. 
// Save data if appropriate. See also applicationDidEnterBackground:.
//程序在终止时执行，包括正常终止或异常终止，例如说一个应用程序在后太运行（例如音乐播放软件、社交软件等）占用太多内存这时会意外终止调用此方法；
- (void)applicationWillTerminate:(UIApplication *)application
{
    
}

@end