我理解这个错误的含义.我在stackoverflow.com上发现了许多类似的问题,我试图实现建议的答案,但我仍然收到此错误.我想要做的是使用php web服务我从mysql数据库服务器中提取数据并尝试使用AsyncTask在listview中显示它,如下所示:
class LoadAllProducts extends AsyncTask<String, String, ArrayList<HashMap<String, String>>>
{
ArrayList<HashMap<String, String>> mylist = new ArrayList<HashMap<String, String>>();
protected ArrayList<HashMap<String, String>> doInBackground(String... args)
{
List<NameValuePair> params = new ArrayList<NameValuePair>();
JSONObject json = jParser.makeHttpRequest(url_all_products, "GET", params);
Log.d("All Products: ", json.toString());
try {
JSONArray files = json.getJSONArray(TAG_FILES);
for(int i=0;i<files.length();i++)
{
HashMap<String, String> map = new HashMap<String, String>();
JSONObject e = files.getJSONObject(i);
String file_name = e.getString(TAG_FILE_NAME);
String sender = e.getString(TAG_SENDER);
String subject = e.getString(TAG_SUBJECT);
map.put(TAG_SENDER, sender);
map.put(TAG_SUBJECT, subject);
mylist.add(map);
}
} catch (JSONException e) …
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