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我试图通过 gps 获取地址，将坐标转换为我的位置。我正在使用这段代码：

latitude1 = (location.getLatitude());
        longitude2= (location.getLongitude());

        JSONObject ret = getLocationInfo(); 
        JSONObject location2;
        String location_string;
        try {
            location2 = ret.getJSONArray("results").getJSONObject(0);
            location_string = location2.getString("formatted_address");
            Log.d("test", "formattted address:" + location_string);
            StringRua = (" " + location_string);
        } catch (JSONException e1) {
            e1.printStackTrace();

        }

和

public JSONObject getLocationInfo() 
{
        HttpGet httpGet = new HttpGet("http://maps.google.com/maps/api/geocode/json?latlng="+latitude1+","+longitude2+"&sensor=true");
        HttpClient client = new DefaultHttpClient();
        HttpResponse response;
        StringBuilder stringBuilder = new StringBuilder();

    try {
        response = client.execute(httpGet);
        HttpEntity entity = response.getEntity();
        InputStream stream = entity.getContent();
        int b;
        while ((b = stream.read()) != -1) {
            stringBuilder.append((char) b);
        }
    } catch (ClientProtocolException e) {
        } catch (IOException e) {
    }

    JSONObject jsonObject = new JSONObject();
    try {
        jsonObject = new JSONObject(stringBuilder.toString());
    } catch (JSONException e) {
        e.printStackTrace();
    }
    return jsonObject;
}

它在我的手机中运行良好。但是当我的朋友在执行这部分代码时尝试使用同一个应用程序时，应用程序只是强制关闭。

请记住，我已经尝试使用：

Geocoder geocoder = new Geocoder(this, Locale.getDefault());
List<Address> addresses = geocoder.getFromLocation(latitude1, longitude2, 1);

但是执行这个命令太慢了，事实上，它总是返回 null。

谁能帮我？谢谢你

编辑：我刚刚更改了我的代码以使用 asynctask，但现在我没有正确获取位置，它只是说空。

这是我所做的：

private class AsyncCaller extends AsyncTask<Void, Void, Void>
{
    ProgressDialog pdLoading = new ProgressDialog(MainActivity.this);

    @Override
    protected void onPreExecute() {
        super.onPreExecute();

        //this method will be running on UI thread
        pdLoading.setMessage("\tLoading...");
        pdLoading.show();
    }
    @Override
    protected Void doInBackground(Void... params) {

        //this method will be running on background thread so don't update UI frome here
        //do your long running http tasks here,you dont want to pass argument and u can access the parent class' variable url over here


        JSONObject ret = getLocationInfo(); 
        JSONObject location2;
        String location_string;
        try {
            location2 = ret.getJSONArray("results").getJSONObject(0);
            location_string = location2.getString("formatted_address");
            Log.d("test", "formattted address:" + location_string);
            StringRua = (" " + location_string);
        } catch (JSONException e1) {
            e1.printStackTrace();

        }

        return null;
    }

异步任务调用，它位于 AsyncTask 之上：

public JSONObject getLocationInfo() {

    HttpGet httpGet = new HttpGet("http://maps.google.com/maps/api/geocode/json?latlng="+latitude1+","+longitude2+"&sensor=true");
    HttpClient client = new DefaultHttpClient();
    HttpResponse response;
    StringBuilder stringBuilder = new StringBuilder();

    try {
        response = client.execute(httpGet);
        HttpEntity entity = response.getEntity();
        InputStream stream = entity.getContent();
        int b;
        while ((b = stream.read()) != -1) {
            stringBuilder.append((char) b);
        }
    } catch (ClientProtocolException e) {
        } catch (IOException e) {
    }

    JSONObject jsonObject = new JSONObject();
    try {
        jsonObject = new JSONObject(stringBuilder.toString());
    } catch (JSONException e) {
        e.printStackTrace();
    }
    return jsonObject;
}

我正在使用，调用 Async ：

  new AsyncCaller().execute();

" StringRua = (" " + location_string); " 没有得到任何位置

编辑 2：我已将公共 JSONObject getLocationInfo() 放入私有类 AsyncCaller extends AsyncTask {

我只是发现它第一次调用 asynctask 时没有获得位置，但第二次它工作。但我需要在它第一次调用 asynctask 时完成这项工作。OBS：在我朋友的手机中，它不再崩溃，但他总是得到 Null

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1 回答 1

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问题是我猜主 ui 上的网络 I/O，你需要AsyncTask在主线程中执行网络操作，

有关更多信息AsyncTasks

http://developer.android.com/reference/android/os/AsyncTask.html

并且从 Android Honeycomb 及更高版本开始，应用程序将崩溃NetworkOnMainThreadException，但可以在早期版本上运行。

来自开发者参考

This is only thrown for applications targeting the Honeycomb SDK or higher. 
Applications targeting earlier SDK versions are allowed to do networking on 
their main event loop threads, but it's heavily discouraged.

http://developer.android.com/reference/android/os/NetworkOnMainThreadException.html

于 2013-09-07T21:54:28.357 回答