ActivityInfo的获取

        PackageManager pm = getPackageManager();//获取PackageManager实例        List<PackageInfo> pmg = pm.getInstalledPackages(PackageManager.GET_UNINSTALLED_PACKAGES);//获取已经安装的包的信息 Installe 安装        ActivityInfo[] ain;        try {            ain = getPackageManager().getPackageInfo(pmg.get(0).packageName, PackageManager.GET_ACTIVITIES).activities;//直接通过packageManager来获取activityinfo对象            if (ain == null){                Log.d("MainActivity","get activityInfo fail ");            }else                Log.d("MainActivity","activityInfo:  "+ain.length+" "+ ain.hashCode());        } catch (PackageManager.NameNotFoundException e) {            e.printStackTrace();        }