获取进入acticity时间

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
        ActivityManager am = (ActivityManager) getSystemService(this.ACTIVITY_SERVICE);
 
        List<RunningAppProcessInfo> appinfo = am.getRunningAppProcesses();
 
        for (RunningAppProcessInfo runningAppProcessInfo : appinfo) {
            if (runningAppProcessInfo.processName.equals("yourpakagename")) {
                Log.e("TAG", System.currentTimeMillis() + "");
            }
        }
 
    }