android在线时长统计升级版。

前期利用多重标记结合list存储activityname的方式实现的。比较繁琐。升级后，就简单多了。主要是activity生命周期切换和context方法的使用
详细讲解可以参考我的另外一篇文章，https://blog.csdn.net/shoneworn/article/details/80265056

public class OnLineStatics {
private static Context context;
public static boolean mIsAppOnForegroundB;// app是否在前台
public static boolean mIsAppRunningB = false;// APP是否正在运行
private static MetaClass helper ;
private static long mStartTime;
private static Handler mHandler=new Handler(Looper.getMainLooper());// Handler对象

public void init(final Context context, MetaClass metaClass) {
    Application application = (Application) context.getApplicationContext();
    this.context = context;
    //上报活跃量
    this.helper = metaClass;
    application.registerActivityLifecycleCallbacks(new Application.ActivityLifecycleCallbacks() {
        @Override
        public void onActivityCreated(Activity activity, Bundle savedInstanceState) {

        }

        @Override
        public void onActivityStarted(Activity activity) {

        }

        @Override
        public void onActivityResumed(Activity activity) {
            setAppOnForeground(true);
            System.out.println("onlin:onActivityResumed");
        }

        @Override
        public void onActivityPaused(Activity activity) {
            setAppOnForeground(false);
            System.out.println("onlin:onActivityPaused");
        }

        @Override
        public void onActivityStopped(Activity activity) {

        }

        @Override
        public void onActivitySaveInstanceState(Activity activity, Bundle outState) {

        }

        @Override
        public void onActivityDestroyed(Activity activity) {

        }
    });
}


public static boolean mLastAppOnForeground=false;// 缓存上一次app是否在前台
public static Runnable appOnForegroundCheckRunnable=new Runnable() {
    @Override
    public void run() {
        System.out.println("onlin:mIsAppOnForegroundB app是否在前台"+mIsAppOnForegroundB);
        System.out.println("onlin:mLastAppOnForeground 上一次app是否在前台"+mLastAppOnForeground);
        if(mIsAppOnForegroundB!=mLastAppOnForeground){

                if(mIsAppOnForegroundB){
                    helper.reportActive();
                    mStartTime = System.currentTimeMillis()/1000;
                }else{
                    helper.reportOnline(""+(System.currentTimeMillis()/1000 - mStartTime));
                }

            mLastAppOnForeground=mIsAppOnForegroundB;
        }
    }
};

public static void setAppOnForeground(boolean onForeground){
    mIsAppOnForegroundB=onForeground;
    if(mHandler!=null){
        mHandler.removeCallbacks(appOnForegroundCheckRunnable);
        mHandler.postDelayed(appOnForegroundCheckRunnable,1000);
    }
}

}