学步园

我在通过intent 获得传递兑现过的时候报错，空指针,我是getMap方法进行传值，代码如下

public void getMap(View view){
 
        Intent i = new Intent(this, BreweryYourTopBeers.class);
        Log.d("map" , e.beerBreweryId);
        i.putExtra("breweryID",  e.beerBreweryId);
        i.setClass(this, BreweryMap.class);
 
        startActivity(i);
    }

从我的日志中能够看到  在传值之前e.beerBreweryId  确实有值，我在下面的代码中获取改值

public class BreweryMap extends ActionbarMenu {
    BeerData e;
     String beerID;
     GoogleMap map;
    //从bundle  中获得beer  详细信息
     protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_brewerymap);
        //get brewery data
        //get beer data
         Intent intent = getIntent();
         Bundle extras = intent.getExtras();
  
        String breweryID = extras.getString("brewreyID");
        map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)).getMap();
         String url = "http://api.brewerydb.com/v2/brewery/"+ breweryID +"?key=myKey&format=json&withLocations=y";
        Log.d("map", url);
         new myAsyncTask(this,map).execute(url);
}
}

我每次获得值都是NULL ，不知道是什么原因.