获取应用的版本号

/**
* Retrieves application's version number from the manifest
* 
* @return versionName
*/
public String getVersion() {
String version = "0.0.0";
try {
PackageInfo packageInfo = getPackageManager().getPackageInfo(
getPackageName(), 0);
version = packageInfo.versionName;
} catch (NameNotFoundException e) {
e.printStackTrace();
}


return version;
}