android_updateversioncode

PackageManager pm =getPackageManager();
   try {
     //获得包信息，包含版本号和版本名
     PackageInfo packageInfo = pm.getPackageInfo(getPackageName(), 0);
     int versionCode = packageInfo.versionCode;
     String versionName = packageInfo.versionName;
   } catch (NameNotFoundException e) {
    //找不到包异常
    e.printStackTrace();
}