現在我們來學習一下如何實現上一篇中提到的頁面統計和事件追蹤

      在開始之前你需要確保以下四項：

      iOS Developer SDK 4.0 or later；
      Google Analytics for Mobile Apps iOS SDK v2；
      An iOS app that you want to measure using Google Analytics；
      A new Google Analytics app property and profile.

      第一項貌似都差不多是ios5.0以後了；

      第二項sdk的連結在下方“準備開始”的第二項中；

      第三項和第四項可以同時完成，需要填寫你需要使用GA的app的資訊，並且獲得一個trakerId，具體步驟如下：

     1.登入你的GA賬戶(谷歌郵箱登入)，如果是第一次登入,右上角會有一個註冊GA的按鈕，點選按鈕；

     2.之後如下所示：

       當然選擇“應用”了，應用名稱“SammyDress”（這是我的應用名），行業類別（你做什麼的就填什麼），賬戶名稱，這個我後來發現其實是可以多個的，每個賬戶下又可以有多個應用，所以你覺得怎麼好分類就寫什麼名稱。最後，點選"獲取跟蹤ID".

        這個"UA-XXXXXX-1"就是追蹤ID（trakerId）了，下面會用到的（這個介面也可以下載GA ios sdk）。

準備開始（真的開始了）

一、需要下載

二、將sdk中的下列檔案拽入你的工程中：

三、GA使用了CoreData andSystemConfiguration框架，所以你需要將CoreData.framework和SystemConfiguration.framework也新增到你的工程裡。

四、Initialize the tracker(初始化追蹤者)

To initialize the tracker, import theGAI.hheader in your applicationdelegate.mfile and add this code to your application delegate'sapplication:didFinishLaunchingWithOptions:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {  
  // Optional: automatically send uncaught exceptions to Google Analytics.  
  [GAI sharedInstance].trackUncaughtExceptions = YES;  
  // Optional: set Google Analytics dispatch interval to e.g. 20 seconds.  
  [GAI sharedInstance].dispatchInterval = 20;  
  // Optional: set debug to YES for extra debugging information.  
  [GAI sharedInstance].debug = YES;  
  // Create tracker instance.  
  id<GAITracker> tracker = [[GAI sharedInstance] trackerWithTrackingId:@"UA-YOUR-TRACKING-ID"];  
}

id<GAITracker> tracker = [[GAI sharedInstance] defaultTracker];  

       做完以上這些，你就基本做好準備工作了，下面我們來實現螢幕跟蹤，事件追蹤，電子商務分析等資料互動。

1.Add screen measurement(螢幕測量，感覺翻譯怪怪的，可以理解為跟蹤當前在哪個檢視)

      To automatically measure views in your app, have your view controllers extend GAITrackedViewController, a convenience class that extends UIViewController, and provide the view name to give to each view controller in your reports. Each time that view is loaded, a screen view will be sent to Google Analytics.

      For example, suppose you have an “About” view that you want to measure with a view controller header that looks like this:

@interface AboutViewController : UIViewController 

#import "GAITrackedViewController.h"  
@interface AboutViewController : GAITrackedViewController  

- (void)viewDidLoad   
{  
  [super viewDidLoad];  
  self.trackedViewName = @"About Screen";  
}  

[[[GAI sharedInstance] defaultTracker] sendView:@"About"];  

到這裡基本實現了頁面統計分析，去GA頁面檢視一下，你會發現它告訴你你去過“About”介面了。

2.事件追蹤

      通過前面的例子，相信大家已經瞭解到事件追蹤的作用了。現在來講一下如何實現,下面是實現的方法以及引數說明：

/*!  
 Track an event.  
  
 If [GAI optOut] is true, this will not generate any tracking information.  
  
 @param category The event category, or `nil` if none.  
  
 @param action The event action, or `nil` if none.  
  
 @param label The event label, or `nil` if none.  
  
 @param value The event value, to be interpreted as a 64-bit signed integer, or  
 `nil` if none.  
  
 @return `YES` if the tracking information was queued for dispatch, or `NO` if  
 there was an error (e.g. the tracker was closed).  
 */  
- (BOOL)sendEventWithCategory:(NSString *)category  
                   withAction:(NSString *)action  
                    withLabel:(NSString *)label  
                    withValue:(NSNumber *)value; 

[tracker sendEventWithCategory:@"uiAction"  
                     withAction:@"buttonPress"  
                      withLabel:buttonName  
                      withValue:[NSNumber numberWithInt:100]];  

 Note: The Google Android SDK for iOS may throttle events, as well as other hits, if a large number of send calls are made in a short period of time.

       這樣就可以實現事件追蹤了。