java - 如何将 HTTPClient 移至异步任务

Question

我在使用要转移到 AsyncTask 的方法时遇到问题。我已经完成了 doInBackground，但我需要将方法的其余部分移动到 onPostExecute...我只是不知道如何做。

这是我原来的方法。

private void ShowFuelStopAndRoute(String location) throws IOException {
    Geocoder geocoder = new Geocoder(this, Locale.getDefault());  
    List<Address> addresses;

    addresses = geocoder.getFromLocationName(location, 1);
    if(addresses.size() > 0) {
        BitmapDescriptor subwayBitmapDescriptor = BitmapDescriptorFactory.fromResource(R.drawable.fillingstation);
        currentFuelLat= addresses.get(0).getLatitude();
        currentFuellong= addresses.get(0).getLongitude();
        LatLng toPostion = new LatLng(currentFuelLat, currentFuellong);
        GMapV2Direction md = new GMapV2Direction();
        AsyncDoc asyncDoc = new AsyncDoc(MapViewActivity.this, currentLocation, toPostion, GMapV2Direction.MODE_DRIVING);
        ArrayList<LatLng> directionPoint = md.getDirection(doc);

        PolylineOptions rectLine = new PolylineOptions().width(5).color(Color.BLUE);

        for(int i = 0 ; i < directionPoint.size() ; i++) {          
            rectLine.add(directionPoint.get(i));
        }

        map.addPolyline(rectLine);
        Marker fuelMarker = map.addMarker(new MarkerOptions().position(toPostion).icon(subwayBitmapDescriptor).title("Fueling Station, " + location));


    }
}

我将以下行移动到不同的类和异步类中

Document doc = md.getDocument(currentLocation, toPostion, GMapV2Direction.MODE_DRIVING);

这已被替换为:

return DALController.sharedInstance().getDocument(startLoc, endLoc, mode);

我有这么多 AsyncTask Complete ，如下所示:

    private class AsyncDoc extends AsyncTask<Void, Void, Document > {

        public String mode;
        public LatLng startLoc;
        public LatLng endLoc;


        public AsyncDoc (Activity activity, LatLng startLoc, LatLng endLoc, String mode){

            this.startLoc = startLoc;
            this.endLoc = endLoc;
            this.mode = mode;
            dialog = new ProgressDialog(activity);
        }

        private Activity activity;
        private ProgressDialog dialog;

        protected void onPreExecute() {
            this.dialog.setMessage("Progress start");
            if (! (activity).isFinishing()) {
                this.dialog.show();
            }
        }


        @Override
        protected Document  doInBackground(Void... params) {
                return DALController.sharedInstance().getDocument(startLoc, endLoc, mode);
        }

        @Override
        protected void onPostExecute(Document  result) {

            if (dialog.isShowing()) {
                dialog.dismiss();
            }




        }

    }

但我需要确保在 doInBackground 完成之前其余代码不会运行:

        ArrayList<LatLng> directionPoint = md.getDirection(doc);

        PolylineOptions rectLine = new PolylineOptions().width(5).color(Color.BLUE);

        for(int i = 0 ; i < directionPoint.size() ; i++) {          
            rectLine.add(directionPoint.get(i));
        }

        map.addPolyline(rectLine);
        Marker fuelMarker = map.addMarker(new MarkerOptions().position(toPostion).icon(subwayBitmapDescriptor).title("Fueling Station, " + location));

如何确保 doInBackground 在 showfuelstopandroute 方法的其余部分完成之前完成？

Answer 1

How can I ensure the doInBackground completes before the rest of my showfuelstopandroute method completes?

您应该需要将所有代码移至 onPostExecute 内，以便在 doInBackground 执行完成后执行。如:

@Override
   protected void onPostExecute(Document  result) {

        if (dialog.isShowing()) {
            dialog.dismiss();
          }
         // do your work here after doInBackground execution
          ArrayList<LatLng> directionPoint = md.getDirection(result);
          ....

     }