Question

https://stackoverflow.com/a/14164318/3575963

在这里，他使用了

View myFragmentView = inflater.inflate(R.layout.fragment_a, container, false);

来自父类。我的父母也没有inflater，这是一张地图。

来自asynctask doitbackground，我在textview返回了5个arraylists以postexecute。

但是我做不到因为我不能使用findviewbyid，因为我无法获得活动。我有上下文，但没有做任何事情。

这是我的postexecute

  protected void onPostExecute(Wrapper wrap){

     TextView name = new TextView (mContext);
     TextView type = new TextView (mContext);
     TextView location = new TextView (mContext);
     TextView distance = new TextView (mContext);

     List<Double> dist = new ArrayList();
     List<String> loc = new ArrayList();
     List<String> nme = new ArrayList();
     List<String> typ = new ArrayList();
     List<Calendar> start = new ArrayList();
     List<Calendar> endd = new ArrayList();

     dist = wrap.getDist();
     loc = wrap.getLocation();
     nme = wrap.getName();
     typ = wrap.getType();
     start = wrap.getsDate();
     endd = wrap.geteDate();
     int idx = -1;
     LinearLayout shw_evnt = (LinearLayout) shw_evnt.findViewById(R.id.);

      for(Double dis:dist){
         idx++;
         name.setText(nme.get(idx));
         type.setText(typ.get(idx));
         location.setText(loc.get(idx));
         distance.setText(dist.get(idx).toString()+" meters");

这部分是错误的

 LinearLayout shw_evnt = (LinearLayout) shw_evnt.findViewById(R.id.);

我尝试了其他的东西，但它没有用。我将使用之前未使用的其他布局。

show_events.xml：

  <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent" android:layout_height="match_parent">
    android:id="@+id/shwevnt"

</LinearLayout>

此处来电地图活动类

 public class MapActivity extends AppCompatActivity  implements GoogleApiClient.ConnectionCallbacks,
        GoogleApiClient.OnConnectionFailedListener {
    private int strokeColor = 0xffff0000; //red outline
    private int shadeColor = 0x44ff0000; //opaque red fill
    private int count=0;
    private GoogleMap googleMap;
    private GoogleApiClient mGoogleApiClient;
    private Location mLastLocation;
    private LocationRequest mLocationRequest;
    private Context mContext;
    private String TAG = "Chic";
    private final static int CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000;
    private int radius;//in meters
    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    protected void onCreate(Bundle savedInstanceState) {
        Log.d(TAG, "inside map oncreaste");
        mContext =  getApplicationContext();
        View myFragmentView = inflater.inflate(R.layout.show_events, container, false);
        super.onCreate(savedInstanceState);
        setUpMapIfNeeded();
        Log.d(TAG, "buildgoogleapi called");
        buildGoogleApiClient();
        Log.d(TAG, "after buildgoogleapi called");
     }//end of oncreate

这里的错误

View myFragmentView = inflater.inflate(R.layout.show_events, container, false);

因为我没有inflater

我不想从postexecute返回到主类或其他包装类。我想我可以在postexecute里面做，不能吗？

LayoutInflater inflater = (LayoutInflater)context.getSystemService
  (Context.LAYOUT_INFLATER_SERVICE);

如果我这样做，我将采用当前视图，而不是我想创建的视图？

我试过

private Inflater inflater;
     View myFragmentView = inflater.inflate(R.layout.show_events, container, false);

Answer 1

是的，只需将Activity传递给Asynctask：

即可

   AsyncTask myAsyncTask = new MyTask(this);

然后你会在layout的{{1}}内找到该元素：

Activity

像丹尼尔描述这将是一种不好的做法。

我建议你 Interface。

例如：

a）创建接口类。

public class MyTask extends AsyncTask<String, String, String>{
    public MyActivity activity;

    public MyTask(MyActivity a){
        this.activity = a;
    }
    protected void onPostExecute(String result){
...
...
       LinearLayout shw_evnt = (LinearLayout) activity.findViewById(R.id.shwevnt);
...
...
    }
}

b）转到AsyncTask类，并将接口AsyncResponse声明为字段：

public interface AsyncResponse {
    void processFinish(String output);
}

c）在您的主Activity中，您需要实现AsyncResponse接口。

public class MyAsyncTask extends AsyncTask{
    public AsyncResponse delegate = null;
    @Override
    protected void onPostExecute(String result) {
         delegate.processFinish(result);
    }
}

Answer 2

这是解决方案..

some_dict = {'a':{}, b:{}}

Answer 3

只需将Activity作为参数传递给AsyncTask类。见here。请注意，将上下文存储为成员变量的不良做法是因为上下文可能会发生变化。

无法在AsyncTask中访问“findViewById”

3 个答案:

我建议你 Interface。