需要幫助的JSON解析

Question

我有我的JSON文件是這樣的：

{ 
    "shops": [ 
     { 
     "id": "11", 
     "name": "Next", 
     "description": "Opened in 2005, offers a selection of clothes, shoes and accessories.", 
     "url": "/shop/550/127", 
     "categories": [ 
      "4", 
      "33", 
      "34", 
      "16" 
     ], 
     "bg_image": "/uploads/static/shop/460px/2012/12/5385-127-sale.jpg" 
     }, 
..... 

我想根據使用「類別」的類別來獲取這個商店。例如，如果男士的牛仔褲從列表中點擊，則與該類別關聯的所有商店顯示爲列表。而這個JSON文件存儲在SD卡中。目前，如果點擊列表項，我可以獲取所有商店。但我無法根據類別進行過濾。

Jean.java

import java.io.BufferedReader; 
import java.io.File; 
import java.io.FileNotFoundException; 
import java.io.FileReader; 
import java.io.IOException; 
import java.util.HashMap; 
import java.util.List; 

import org.json.JSONObject; 

import com.kabelash.sg.util.ExternalStorage; 

import android.app.Activity; 
import android.os.AsyncTask; 
import android.os.Bundle; 
import android.util.Log; 
import android.view.Menu; 
import android.widget.ListView; 
import android.widget.SimpleAdapter; 

public class Jeans extends Activity { 
    private final String JSON_file = "api_output_example.json"; 
    File jsonFile; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.baby1_1); 

     /** Getting Cache Directory */ 
     File cDir = ExternalStorage.getSDCacheDir(this, "json_files"); 

     /** Getting a reference to temporary file, if created earlier */ 
     jsonFile = new File(cDir.getPath() + "/" + JSON_file) ; 

     String strLine=""; 
     StringBuilder strJson = new StringBuilder(); 

     /** Reading contents of the temporary file, if already exists */ 
     try { 
      FileReader fReader = new FileReader(jsonFile); 
      BufferedReader bReader = new BufferedReader(fReader); 

      /** Reading the contents of the file , line by line */ 
      while((strLine=bReader.readLine()) != null ){ 
       strJson.append(strLine); 
      } 
     } catch (FileNotFoundException e) { 
      e.printStackTrace(); 
     }catch(IOException e){ 
      e.printStackTrace(); 
     } 


    //System.out.println(strJson); 

     /** Start parsing JSON data */ 
     new ListViewLoaderTask().execute(strJson.toString()); 

    } 


    private class ListViewLoaderTask extends AsyncTask<String, Void, SimpleAdapter>{ 

     JSONObject jObject; 
     /** Doing the parsing of JSON data in a non-ui thread */ 
     @Override 
     protected SimpleAdapter doInBackground(String... strJson) { 
      try{ 
       jObject = new JSONObject(strJson[0]); 
       CountryJSONParser countryJsonParser = new CountryJSONParser(); 
       countryJsonParser.parse(jObject); 
      }catch(Exception e){ 
       Log.d("JSON Exception1",e.toString()); 
      } 

      CountryJSONParser countryJsonParser = new CountryJSONParser(); 

      List<HashMap<String, String>> shops = null; 

      try{ 
       /** Getting the parsed data as a List construct */ 
       shops = countryJsonParser.parse(jObject); 
      }catch(Exception e){ 
       Log.d("Exception",e.toString()); 
      } 

      /** Keys used in Hashmap */ 
      String[] from = { "shop","image","description"}; 

      /** Ids of views in listview_layout */ 
      int[] to = { R.id.tv_country,R.id.iv_flag,R.id.tv_country_details}; 

      /** Instantiating an adapter to store each items 
      * R.layout.listview_layout defines the layout of each item 
      */ 
      SimpleAdapter adapter = new SimpleAdapter(getBaseContext(), shops, R.layout.lv_layout, from, to); 

      return adapter; 
     } 

     /** Invoked by the Android system on "doInBackground" is executed completely */ 
     /** This will be executed in ui thread */ 
     @Override 
     protected void onPostExecute(SimpleAdapter adapter) { 

      /** Getting a reference to listview of main.xml layout file */ 
      ListView listView = (ListView) findViewById(R.id.lv_countries); 

      /** Setting the adapter containing the country list to listview */ 
      listView.setAdapter(adapter); 
     } 
    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     getMenuInflater().inflate(R.menu.main, menu); 
     return true; 
    } 
} 

countryJSONParser.java

import java.util.ArrayList; 
import java.util.HashMap; 
import java.util.List; 

import org.json.JSONArray; 
import org.json.JSONException; 
import org.json.JSONObject; 

public class CountryJSONParser { 

    /** Receives a JSONObject and returns a list */ 
    public List<HashMap<String,String>> parse(JSONObject jObject){  

     JSONArray jShops = null; 
     try {   
      /** Retrieves all the elements in the 'countries' array */ 
      jShops = jObject.getJSONArray("shops"); 
     } catch (JSONException e) { 
      e.printStackTrace(); 
     } 
     /** Invoking getShops with the array of json object 
     * where each json object represent a country 
     */ 
     return getShops(jShops); 
    } 


    private List<HashMap<String, String>> getShops(JSONArray jShops){ 
     int shopCount = jShops.length(); 
     List<HashMap<String, String>> shopList = new ArrayList<HashMap<String,String>>(); 
     HashMap<String, String> shop = null;  

     /** Taking each shop, parses and adds to list object */ 
     for(int i=0; i<shopCount;i++){ 
      try { 
       /** Call getShop with shop JSON object to parse the shop */ 
       shop = getShop((JSONObject)jShops.get(i)); 
       shopList.add(shop); 

      } catch (JSONException e) { 
       e.printStackTrace(); 
      } 
     } 

     return shopList; 
    } 

    /** Parsing the shop JSON object */ 
    private HashMap<String, String> getShop(JSONObject jShop){ 

     HashMap<String, String> shop = new HashMap<String, String>(); 
     String shopName = ""; 
     String image=""; 
     String description = ""; 
     String categories = ""; 
     //String capital = "";  

     try { 
      shopName = jShop.getString("name"); 
      image = jShop.getString("bg_image_small"); 
      description = jShop.getString("description"); 
      categories = jShop.getString("categories"); 

      String details =  "Description : " + description; 
      //if (categories.equals("11")){ 
      shop.put("shop", shopName); 
      shop.put("image", image); 
      shop.put("description", details); 
      shop.put("categories", categories); 
      //} 
     } catch (JSONException e) {   
      e.printStackTrace(); 
     }  
     return shop; 
    } 
} 

上面給出的代碼工作正常，但我想知道如何對其進行過濾。我想用「bg_image」鏈接在圖像上顯示圖像（圖像存儲在SD卡上）。有人可以根據我的要求編輯此代碼嗎？ （很遺憾，我在Google上找不到任何有用的東西）。請幫忙！

編輯︰現在我試圖做這樣的事情，但不能正確。

import java.util.ArrayList; 
import java.util.HashMap; 
import java.util.List; 

import org.json.JSONArray; 
import org.json.JSONException; 
import org.json.JSONObject; 

public class ShopJSONParser { 
    public class Shop { 
     public String name; 
     public String category; 
     public String description; 
     public String image; 
     public ArrayList<String> category_list; 
    } 
    /** Receives a JSONObject and returns a list */ 
    public List<HashMap<String,String>> parse(JSONObject jObject){  

     JSONArray jShops = null; 
     try {   
      // Retrieves all the elements in the 'shops' array 
      jShops = jObject.getJSONArray("shops"); 
     } catch (JSONException e) { 
      e.printStackTrace(); 
     } 
     // Invoking getShops with the array of json object 
     // where each json object represent a shop 
     return getShops(jShops); 
    } 

    ArrayList<Shop> shops_array = new ArrayList<Shop>(); 
    private List<HashMap<String, String>> getShops(JSONArray jShops){ 
     int shopCount = jShops.length(); 
     List<HashMap<String, String>> shopList = new ArrayList<HashMap<String,String>>(); 
     HashMap<String, String> shop = null;  

     /** Taking each shop, parses and adds to list object */ 
     for (int i = 0; i < jShops.length(); i++) { 
      JSONObject Shop_json_obj = jShops.getJSONObject(i); 
      Shop shop1 = new Shop(); 

      String name = Shop_json_obj.getString("name"); 
      String description = Shop_json_obj.getString("description"); 

      shop1.name = name; 
      shop1.description = description; 

      shop1.category_list = new ArrayList<String>(); 
      JSONArray categories_json_array = null; 

      categories_json_array = shop1.getJSONArray("categories"); 

      for (int j = 0; j < categories_json_array.length(); j++) { 

       String cat = categories_json_array.getString(j); 
       shop1.category_list.add(cat); 
      } 

      shops_array.add(shop1); 

     } 

     return shopList; 
    } 

    /** Parsing the shop JSON object */ 
    private HashMap<String, String> getShop(JSONObject jShop){ 

     HashMap<String, String> shop = new HashMap<String, String>(); 
     String shopName = ""; 
     String image=""; 
     String description = ""; 
     String categories = ""; 

     try { 
      shopName = jShop.getString("name"); 
      image = jShop.getString("bg_image_small"); 
      description = jShop.getString("description"); 
      categories = jShop.getJSONArray("categories").toString(); 
      System.out.println(categories); 
      String details =  "Description : " + description; 
      //if (categories.equals("13")){ 
      shop.put("shop", shopName); 
      shop.put("image", image); 
      //shop.put("description", details); 
      //shop.put("categories", categories); 
      //} 
     } catch (JSONException e) {   
      e.printStackTrace(); 
     }  
     return shop; 
    } 
} 

需要進一步的幫助。謝謝。

Answer 1

首先，我認爲你解析錯了。 'categories'是JsonArray，當你將它解析爲一個字符串時。你應該做一個數組。所以，它基本上是一個數組內的數組。完成之後，您可以根據類別值輕鬆標記單個項目作爲適當的類別。

編輯：

一個更好的方式來做到這將是創建具有所需屬性的網店對象，然後填充車間對象的名單在你的JSON解析功能。 e.g

public class Shop{ 

    public String name; 
    public String description; 
    public String image; 
    public ArrayList<String> category_list; 

    public Shop(){ 
     category_list = new ArrayList<String>(); 
    } 

} 

，這裏是你的修改CountryJSONParser：

import java.util.ArrayList; 
import org.json.JSONArray; 
import org.json.JSONException; 
import org.json.JSONObject; 

public class CountryJSONParser { 

    /** Receives a JSONObject and returns a list */ 
    public ArrayList<Shop> parse(JSONObject jObject){  

     JSONArray jShops = null; 
     try {   
      /** Retrieves all the elements in the 'countries' array */ 
      jShops = jObject.getJSONArray("shops"); 
     } catch (JSONException e) { 
      e.printStackTrace(); 
     } 
     /** Invoking getShops with the array of json object 
     * where each json object represent a country 
     */ 
     return getShops(jShops); 
    } 

    private ArrayList<Shop> getShops(JSONArray jShops){ 
     int shopCount = jShops.length(); 
     ArrayList<Shop> shops_array = new ArrayList<Shop>(); 
     Shop shop = new Shop(); 

     /** Taking each shop, parses and adds to list object */ 
     for(int i=0; i<shopCount;i++){ 
      try { 
       /** Call getShop with shop JSON object to parse the shop */ 
       shop = getShop((JSONObject)jShops.get(i)); 
       //shopList.add(shop); 
       shops_array.add(shop); 

      } catch (JSONException e) { 
       e.printStackTrace(); 
      } 
     } 

     return shops_array; 
    } 

    /** Parsing the shop JSON object */ 
    private Shop getShop(JSONObject jShop){ 

     Shop shop = new Shop(); 

     try { 
     shop.name = jShop.getString("name"); 
      shop.image = jShop.getString("bg_image_small"); 
      String details =  "Description : " + shop.description; 
      shop.description = details; 

      shop.category_list = new ArrayList<String>(); 
      JSONArray categories_json_array = null; 

      categories_json_array = jShop.getJSONArray("categories"); 

      for (int j = 0; j < categories_json_array.length(); j++) { 

       String cat = categories_json_array.getString(j); 
       shop.category_list.add(cat); 
      } 

     } catch (JSONException e) {   
      e.printStackTrace(); 
     }  
     return shop; 
    } 
}