i'm trying to post data to my php-file using json. In my php-file, I want to use the posted data for a mySQL-Select-Statement and return the selection to my code and displaying it as a list.

What is the simpliest way to do it?

This is my 'postData()':

   public void postData() {
    //trying
    List<Map<String, String>> buyCategories = new ArrayList<Map<String, String>>();
    //trying

    try{
        // url where the data will be posted
        String postReceiverUrl = "http://www.url.de/getArticles.php";

        // HttpClient
        HttpClient httpClient = new DefaultHttpClient();

        // post header
        HttpPost httpPost = new HttpPost(postReceiverUrl);

        int cat = UsingSharedPrefs.getChosenCategorie();
        if(cat == 0) {
            cat = 100;
        }
        String cats = Integer.toString(cat);

        // add your data
        List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
        nameValuePairs.add(new BasicNameValuePair("categorieId", cats));

        httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

        // execute HTTP post request
        HttpResponse response = httpClient.execute(httpPost);
        HttpEntity resEntity = response.getEntity();

        if (resEntity != null) {

            JSONObject jsonResponse = new JSONObject(jsonResult);
            JSONArray jsonMainNode = jsonResponse.getJSONArray("testproducts");
            for (int i = 0; i < jsonMainNode.length(); i++) {
                JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
                String name = jsonChildNode.getString("testproduct_name");
                String price = jsonChildNode.getString("testproduct_price");
                String path = jsonChildNode.getString("testproduct_buffer");

                HashMap<String, String> hmBuyCategories = new HashMap<String,String>();
                hmBuyCategories.put("txt", "Categorie : " + name);
                hmBuyCategories.put("pri", "Price : " + price);
                hmBuyCategories.put("bes","Currency : " + path);

                int imageId = getResources().getIdentifier("jollocks.logle:drawable/" + path, null, null);

                hmBuyCategories.put("pic", Integer.toString(imageId) );

                buyCategories.add(hmBuyCategories);
                }
            String responseStr = EntityUtils.toString(resEntity).trim();
            Log.v(TAG, "Response: " +  responseStr);
        }

    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    } catch (JSONException e) {
        Toast.makeText(getApplicationContext(), "Errortest" + e.toString(),
        Toast.LENGTH_SHORT).show();
    }

    String[] from = { "pic","txt","pri", "bes" };

    int[] to = { R.id.buffer,R.id.name, R.id.price, R.id.beschreibung};

    ListView listView = ( ListView ) findViewById(R.id.sampleListView);

    SimpleAdapter simpleAdapter = new SimpleAdapter(this, buyCategories,
    R.layout.list_item_product,
    from, to);
    listView.setAdapter(simpleAdapter);
}

You can use volley library. Android volley is a networking library was introduced to make networking calls much easier, faster without writing tons of code. By default all the volley network calls works asynchronously, so we don’t have to worry about using asynctask anymore.

http://developer.android.com/training/volley/simple.html

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