私はAndroidプログラミングの初心者です。JSON を使用して MySQL データベースからの ID 識別子をスローしようとしています。listView に対応するデータを Toast に表示するにはどうすればよいですか? 私は本当に助けが必要です:(
// Async Task to access the web
@SuppressLint("NewApi")
private class JsonReadTask extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... params) {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
nameValuePairs = new ArrayList<NameValuePair>(2);
nameValuePairs.add(new BasicNameValuePair("stud_id",MainActivity.user_id));
try {
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
} catch (UnsupportedEncodingException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
try {
HttpResponse response = httpclient.execute(httppost);
jsonResult = inputStreamToString(
response.getEntity().getContent()).toString();
}
catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
private StringBuilder inputStreamToString(InputStream is) {
String rLine = "";
StringBuilder answer = new StringBuilder();
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
try {
while ((rLine = rd.readLine()) != null) {
answer.append(rLine);
}
}
catch (IOException e) {
}
return answer;
}
@Override
protected void onPostExecute(String result) {
ListDrawer();
}
}// end async task
public void accessWebService() {
try{
JsonReadTask task = new JsonReadTask();
// passes values for the urls string array
task.execute(new String[] { url });
}catch(Exception e){
Toast.makeText(getActivity(), e.getMessage().toString() + " 3", Toast.LENGTH_LONG).show();
}
}
// build hash set for list view
public void ListDrawer() {
List<Map<String, String>> classList = new ArrayList<Map<String, String>>();
try {
JSONObject jsonResponse = new JSONObject(jsonResult);
JSONArray jsonMainNode = jsonResponse.optJSONArray("recipient");
for (int i = 0; i < jsonMainNode.length(); i++) {
JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
String friend = jsonChildNode.optString("last_name") + ", " + jsonChildNode.optString("first_name");
String outPut = friend;
classList.add(createMsgList("recipient", outPut));
}
} catch (JSONException e) {
Toast.makeText(getActivity(), e.getMessage().toString() + " 1", Toast.LENGTH_LONG).show();
}
try{
SimpleAdapter simpleAdapter = new SimpleAdapter(getActivity() , classList,
android.R.layout.simple_list_item_1, new String[] { "recipient" }, new int[] { android.R.id.text1 });
listView.setAdapter(simpleAdapter);
listView.setOnItemClickListener(new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> a, View v, int i,
long l) {
// TODO Auto-generated method stub
Toast.makeText(getActivity(), listView.getId(), Toast.LENGTH_LONG).show();
}
});
}catch(Exception e){
Toast.makeText(getActivity(), e.getMessage().toString() + " 2", Toast.LENGTH_LONG).show();
}
}
private HashMap<String, String> createMsgList(String name, String subject) {
HashMap<String, String> friendList = new HashMap<String, String>();
friendList.put(name, subject);
return friendList;
}
}