如何使用JSON对象传递JSON数组 [英] How to Pass JSON Array using JSON Object
问题描述
GridView控件包含类别，当我做水龙头上的任何GridView的项目（即 - 任何类别）。我想证明这些物品属于只在ViewPager特定类别
例如，我有两个类别第一 - 电子和第二 - 家电，仍然每当我做水龙头在家电类别 - 它显示所有的项目（从电子1到电器2 ），而它显示唯一项目那些下的家电类别
问题
仍然显示在ViewPager的所有项目，无论哪一类已被用户窃听.... 如何可以我证明这些物品属于窃听类别只？
公共类MainActivity延伸活动{ ArrayList的＆LT;项目＆GT; itemsArrayList;
... @覆盖
保护无效的onCreate（捆绑savedInstanceState）{
super.onCreate（savedInstanceState）; 的setContentView（R.layout.activity_main）; itemsArrayList =新的ArrayList＆LT;项目＆GT;（）; ... gridView.setOnItemClickListener（新OnItemClickListener（）{ @覆盖
公共无效onItemClick（适配器视图＆LT;＆GT;为arg0，ARG1查看，INT位置，
长ID）{ 。字符串categoryName = menusArrayList.get（位置）.getName（）的toString（）;
Log.d（类别名称，类别名称）; 菜单= menusArrayList.get（位置）;
itemsArrayList = menus.getItemsArrayList（）; 适配器=新ViewPagerAdapter（MenusActivity.this，R.layout.adapter_viewpager，itemsArrayList）; viewPager.setAdapter（适配器）;
}
}）;
}
类JSONAsyncTask扩展的AsyncTask＆LT;弦乐，太虚，布尔＆GT; { ProgressDialog对话框; @覆盖
在preExecute保护无效（）{
super.on preExecute（）; } @覆盖
保护布尔doInBackground（字符串的URL ...）{
尝试{ ..... JSONArray jsonArray = jsonObject.getJSONArray（类）; 的for（int i = 0; I＆LT; jsonArray.length（）;我++）{
JSONObject的jObject = jsonArray.getJSONObject（I） 菜单=新菜单（）; menus.setName（jObject.getString（名字））;
menus.setImage（jObject.getString（图像））; JSONArray imagesArray = jObject.getJSONArray（项目）; 对于（INT J = 0; J＆LT; imagesArray.length（）; J ++）
{
JSONObject的imagesObject = imagesArray.getJSONObject（J）; 项目=新项目（）;
items.setTitle（imagesObject.getString（标题））;
items.setImage（imagesObject.getString（图像））; itemsArrayList.add（项目）;
} menus.setItemsArrayList（itemsArrayList）;
menusArrayList.add（菜单）;
}
返回true;
}
...
返回false;
} 保护无效onPostExecute（布尔结果）{
dialog.cancel（）;
... }
}}
您itemArrayList是全球性的，并在解析你每次你读一个类别时将项目添加到该列表。出于这个原因，你itemListArray包含的所有项目。既然是参考列表时，您将项目添加到列表中，你也增加项目previous类，因为它们引用相同的列表。试着改变你的内循环是这样的。
的ArrayList＆LT;项目＆GT; itemsArrayList =新的ArrayList＆LT;项目＆GT;（）;
对于（INT J = 0; J＆LT; imagesArray.length（）; J ++）
{
JSONObject的imagesObject = imagesArray.getJSONObject（J）; 项目=新项目（）;
items.setTitle（imagesObject.getString（标题））;
items.setImage（imagesObject.getString（图像））; itemsArrayList.add（项目）;
}
GridView contains Categories, and when I do tap on any of the GridView item (i.e - any Category) i would like to show items those belongs to that particular Category only in ViewPager.
For example, I have two categories first - Electronics and second - Appliances, still whenever i do tap on Appliances category - it showing all the items (from Electronics 1 to Appliances 2) whereas it has to show only items those are under Appliances category
ISSUE
Still showing all the items in a ViewPager, no matter which category has been tapped by user.... How may i show those Items that belongs to tapped Category only ?
public class MainActivity extends Activity {
ArrayList<Items> itemsArrayList;
...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
itemsArrayList = new ArrayList<Items>();
...
gridView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int position,
long id) {
String categoryName = menusArrayList.get(position).getName().toString();
Log.d("categoryName:", categoryName);
menus = menusArrayList.get(position);
itemsArrayList = menus.getItemsArrayList();
adapter = new ViewPagerAdapter(MenusActivity.this, R.layout.adapter_viewpager, itemsArrayList);
viewPager.setAdapter(adapter);
}
});
}
class JSONAsyncTask extends AsyncTask<String, Void, Boolean> {
ProgressDialog dialog;
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected Boolean doInBackground(String... urls) {
try {
.....
JSONArray jsonArray = jsonObject.getJSONArray("category");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jObject = jsonArray.getJSONObject(i);
menus = new Menus();
menus.setName(jObject.getString("name"));
menus.setImage(jObject.getString("image"));
JSONArray imagesArray = jObject.getJSONArray("items");
for(int j=0; j<imagesArray.length(); j++)
{
JSONObject imagesObject = imagesArray.getJSONObject(j);
items = new Items();
items.setTitle(imagesObject.getString("title"));
items.setImage(imagesObject.getString("image"));
itemsArrayList.add(items);
}
menus.setItemsArrayList(itemsArrayList);
menusArrayList.add(menus);
}
return true;
}
...
return false;
}
protected void onPostExecute(Boolean result) {
dialog.cancel();
...
}
}
}
Your itemArrayList is global and on parsing you're adding items to that list each time you read a category. For that reason your itemListArray include all items. Since it is reference to a list when you add an item to list, you're also adding item to previous categories since they reference to same list. Try changing your inner loop like this.
ArrayList<Items> itemsArrayList = new ArrayList<Items>();
for(int j=0; j<imagesArray.length(); j++)
{
JSONObject imagesObject = imagesArray.getJSONObject(j);
items = new Items();
items.setTitle(imagesObject.getString("title"));
items.setImage(imagesObject.getString("image"));
itemsArrayList.add(items);
}
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