有用的代码

1. 遍历NavigationController栈中的视图

XXView *rootViewController = nil;for (UIViewController *VC in self.navigationController.viewControllers) {     if ([VC isKindOfClass:[XXView class]]) {         rootViewController = (XXView *)VC;     } } [self.navigationController popToViewController:rootViewController animated:YES];

 2. 背景音乐播放，支持mp3格式
需要先导入框架及代码中#import <AVFoundation/AVFoundation.h>

NSString *musicPath = [[NSBundle mainBundle] pathForResource:@"backgrounmusic" ofType:@"mp3"];NSURL *url = [[NSURL alloc] initFileURLWithPath:musicPath];

AVAudioPlayer *player = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:nil];// 创建播放器self.myBackMusic = player; //赋值给自己定义的类变量[url release];[player release];

[myBackMusic prepareToPlay];[myBackMusic setVolume:1];myBackMusic.numberOfLoops = -1; //设置音乐播放次数  -1为一直循环if(mainMusicStatus){    [myBackMusic play]; //播放}

3. 按钮播放声音、播放短声音

需要导入框架#import <AudioToolbox/AudioToolbox.h>

NSString *thesoundFilePath = [[NSBundle mainBundle] pathForResource:@"Clap Crowd" ofType:@"caf"]; //音乐文件路径CFURLRef thesoundURL = (CFURLRef)[NSURL fileURLWithPath:thesoundFilePath];AudioServesCreateSystemSoundID(thesoundURL, &sameViewSoundID);//变量SoundID与URL对应

AudioServicesPlaySystemSound(sameViewSoundID); //播放SoundID声音

4. 判断网络是否连接

/**** 此函数用来判断是否网络连接服务器正常* 需要导入Reachability类*/

+ (BOOL)isExistenceNetwork{    BOOL isExistenceNetwork;    Reachability *reachability = [Reachability reachabilityWithHostName:@""];  // 测试服务器状态

     switch([reachability currentReachabilityStatus]) {            case NotReachable:                  isExistenceNetwork = FALSE;                  break;             case ReachableViaWWAN:                   isExistenceNetwork = TRUE;                   break;              case ReachableViaWiFi:                    isExistenceNetwork = TRUE;                    break;     }     return  isExistenceNetwork;}

5. 实时通知网络状况

/** 在应用委托的方法didFinishLaunchingWithOptions中添加*/

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(reachabilityChanged:) name:kReachabilityChangedNotification object:nil];reachability = [[Reachability reachabilityWithHostName:@"www.baidu.com"] retain];[reachability startNotifier];........return YES;

/***此函数通过判断联网方式，通知给用户*/- (void)reachabilityChanged:(NSNotification *)notification{      Reachability *curReachability = [notification object];      NSParameterAssert([curReachability isKindOfClass:[Reachability class]]);      NetworkStatus curStatus = [curReachability currentReachabilityStatus];      if(curStatus == NotReachable) {          [DOIN_Util logFax:@"连接失败"];      }}

6. 延时函数和Timer的使用

//延时函数：[NSThread sleepForTimeInterval:5.0]； //暂停5s.

//Timer的使用：NSTimer *connectionTimer;  //timer对象

//实例化timerself.connectionTimer=[NSTimerscheduledTimerWithTimeInterval:1.5 target:selfselector:@selector(timerFired:) userInfo:nil repeats:NO];[[NSRunLoop currentRunLoop]addTimer:self.connectionTimer forMode:NSDefaultRunLoopMode];//用timer作为延时的一种方法   do{[[NSRunLoopcurrentRunLoop]runUntilDate:[NSDatedateWithTimeIntervalSinceNow:1.0]];}while(!done); 

//timer调用函数-(void)timerFired:(NSTimer *)timer{done =YES;}