Android BuildConfig.VERSION_NAME返回null？

Question

我只想在登录屏幕上显示我的版本名称，但是，它始终返回null。我在应用程序的gradle构建中定义了versionName，如下所示：

    defaultConfig {
    applicationId "com.maplesyrupindustries.j.airportmeet"
    minSdkVersion 19
    targetSdkVersion 24
    versionCode 7
    versionName "1.0.6"
    multiDexEnabled true
}

我在登录名的onCreate中调用它：

    String build = BuildConfig.VERSION_NAME;
    Log.e(TAG, BuildConfig.VERSION_NAME);
    tvVersion.setText("Alpha " + build);

但是，构建字符串始终为空。是什么赋予了？

Answer 1

请试试这个

PackageInfo pInfo = getPackageManager().getPackageInfo(getPackageName(), 0);
String version = pInfo.versionName;//Version Name
int verCode = pInfo.versionCode;//Version Code

Answer 2

BuildConfig.VERSION_NAME is not working 
1). In Case when you import Wrong Package Please check your import Package 
2). Please import your application package & solve this issue permanently


  PackageInfo pInfo = null;
  try {
       pInfo = getActivity().getPackageManager().getPackageInfo(getActivity().getPackageName(), 0);
    } catch (Exception e) {
        e.printStackTrace();
    }   

 String versionName = pInfo.versionName;//Version Name
 int versionCode = pInfo.versionCode;//Version Code

 Log.e("keshav"," VERSION_NAME -->" + versionName +"versionCode -> "+versionCode);

输出

E/keshav:  VERSION_NAME -->2.0.4  versionCode -> 26