версия приложения2

String versionName = "null";
int versionCode = -1;

try {
android.content.pm.PackageInfo packageInfo = MainActivity.this.getPackageManager().getPackageInfo(getPackageName(), 0);
versionName = packageInfo.versionName;
versionCode = packageInfo.versionCode;
} catch (android.content.pm.PackageManager.NameNotFoundException e) {
e.printStackTrace();
}