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我重新發布我這裏爲了得到一些幫助。JSON解析器低性能
我做了一個JSON解析器至極返回JSONArray（爲了得到我的WebService的信息）。
我最後的代碼扔了NetworkException錯誤（在版本2.3.3它是長，但良好的工作），當我測試IceScreamSandwich ..
我改變了我的代碼，以阻止它，並嘗試變得更好perfs ..但它仍然沒有工作對我的ICS電話：現在沒有更多的錯誤，但一個ioexcepetion：「失敗的JSON的網址改爲」 ..
我告訴你我的活動：
public class TabNewsJSONParsingActivity extends ListActivity
{
// url to make request
private static String url = "http://developer.prixo.fr/API/GetEvents?zone=8";
//JSON names
private static final String TAG_content = "content";
private static final String TAG_zone = "zone";
private static final String TAG_id = "id";
private static final String TAG_area = "area";
private static final String TAG_title = "title";
private static final String TAG_date = "date";
private static final String TAG_author = "author";
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.onglet_news);
// Hashmap for ListView
ArrayList<HashMap<String, String>> newsList = new ArrayList<HashMap<String, String>>();
// Creating JSON Parser instance
JSONParser jParser = new JSONParser();
// getting JSON string from URL
JSONArray json;
try {
json = jParser.getJSONFromUrl1(url);
for(int i=0; i < json.length(); i++)
{
JSONObject child = json.getJSONObject(i);
String id = child.getString(TAG_id);
String title = child.getString(TAG_title);
String content = child.getString(TAG_content);
String date = child.getString(TAG_date);
String author = child.getString(TAG_author);
String zone = child.getString(TAG_zone);
String area = child.getString(TAG_area);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_content, content);
map.put(TAG_title, title);
map.put(TAG_author, author);
// adding HashList to ArrayList
newsList.add(map);
}
}
catch (JSONException e) {
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(this, newsList,R.layout.onglet_news_listitem,new String[] { TAG_content, TAG_title, TAG_author }, new int[] {R.id.name, R.id.email, R.id.mobile });
setListAdapter(adapter);
// selecting single ListView item
ListView lv = getListView();
// Launching new screen on Selecting Single ListItem
lv.setOnItemClickListener(new OnItemClickListener()
{
public void onItemClick(AdapterView<?> parent, View view,int position, long id) {
// getting values from selected ListItem
String name = ((TextView) view.findViewById(R.id.name)).getText().toString();
String cost = ((TextView) view.findViewById(R.id.email)).getText().toString();
String description = ((TextView) view.findViewById(R.id.mobile)).getText().toString();
// Starting new intent
Intent in = new Intent(getApplicationContext(), TabNewsSingleMenuItemActivity.class);
in.putExtra(TAG_content, name);
in.putExtra(TAG_title, cost);
in.putExtra(TAG_author, description);
startActivity(in);
}
});
}
public boolean onOptionsItemSelected(MenuItem item)
{
//On regarde quel item a été cliqué grâce à son id et on déclenche une action
switch (item.getItemId())
{
case R.id.credits:
//pop up
Toast.makeText(TabNewsJSONParsingActivity.this, "Un delire", Toast.LENGTH_SHORT).show();
return true;
case R.id.quitter:
//Pour fermer l'application il suffit de faire finish()
finish();
return true;
}
return false;
}
}
我的解析器：
公共類JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String jsonstr = "";
public JSONParser() {}
// throws IOException just to tell the caller that something bad happened (and
// what) instead of simply returning 'null' without any more information.
public JSONArray getJSONFromUrl1(String url) throws IOException
{
try
{
// should be a member of the parser to allow multiple calls without recreating the client every time.
DefaultHttpClient httpClient = new DefaultHttpClient();
// Using POST means sending data (or it its not following HTTP RFCs)
//HttpPost httpPost = new HttpPost(url);
HttpGet httpGet = new HttpGet(url);
// Here the client may not be entirely initialized (no timeout, no agent-string).
HttpResponse httpResponse = httpClient.execute(httpGet);
//HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
// The native utility function is also handling other charsets
String httpString = EntityUtils.toString(httpEntity);
return new JSONArray(httpString);
} catch (IOException ioe) {
throw ioe;
} catch (Exception ex) {
throw new IOException("Failed to read JSON from Url");
}
}
}
誰知道得到更好的perfs並使其朗姆酒4.0嗎？ 如何將它與異步任務一起使用？ 感謝
謝謝，我嘗試過，但我在ListAdapter適配器=此編譯錯誤新SimpleAdapter（..）：「SimpleAdapter構造是不確定的」 – eento 2012-07-12 14:01:24
@eento請找到更新的代碼。這是由'this'參數引起的。而是請使用'TabNewsJSONParsingActivity.this' – sunil 2012-07-13 05:21:47