我有一个json，我有通过Json产品的product_id和product_name现在在listview中显示我希望当点击item时，那个产品的id应该在toast中显示。我是android的新手，我无法做到这一点 谁能告诉我怎么能这样做呢
public class CityNameActivity extends ListActivity{
ListView list;
private ProgressDialog pDialog;
// URL to get Cities JSON
private static String url = "http://14.140.200.186/Hospital/get_city.php";
// JSON Node names
private static final String TAG_CITIES = "Cities";
//private static final String TAG_ID = "id";
private static final String TAG_NAME = "city_name";
// Cities JSONArray
JSONArray Cities = null;
// Hashmap for ListView
ArrayList<HashMap<String, String>> citylist;
//ArrayList<String> citylist;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.cityname_activity_main);
ListView listView=getListView();
citylist = new ArrayList<HashMap<String, String>>();
// list.setOnClickListener(this);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Intent in = new Intent(getApplicationContext(),
Specialities_Activity.class);
startActivity(in);}
});
new GetCities().execute();
}
/**
* Async task class to get json by making HTTP call
* */
private class GetCities extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
pDialog = new ProgressDialog(CityNameActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected Void doInBackground(Void... arg0) {
// Creating service handler class instance
ServiceHandler sh = new ServiceHandler();
// Making a request to url and getting response
String jsonStr = sh.makeServiceCall(url, ServiceHandler.GET);
Log.d("Response: ", "> " + jsonStr);
if (jsonStr != null) {
try {
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
Cities = jsonObj.getJSONArray(TAG_CITIES);
// looping through All Cities
for (int i = 0; i < Cities.length(); i++) {
JSONObject c = Cities.getJSONObject(i);
//String id = c.getString(TAG_ID);
String name = c.getString(TAG_NAME);
HashMap<String, String> Cities = new HashMap<String, String>();
Cities.put(TAG_NAME, name);
// adding contact to Cities list
citylist.add(Cities);
}
} catch (JSONException e) {
e.printStackTrace();
}
} else {
Log.e("ServiceHandler", "Couldn't get any data from the url");
}
return null;
}
@Override
protected void onPostExecute(Void result)
{
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
/**`enter code here`
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(CityNameActivity.this, citylist, R.layout.city_list_item, new String[] { TAG_NAME}, new int[] { R.id.name});
setListAdapter(adapter);
} }
服务代码处理程序类：
public class ServiceHandler {
static String response = null;
public final static int GET = 1;
public final static int POST = 2;
public ServiceHandler() {
}
/*
* Making service call
* @url - url to make request
* @method - http request method
* */
public String makeServiceCall(String url, int method) {
return this.makeServiceCall(url, method, null);
}
/*
* Making service call
* @url - url to make request
* @method - http request method
* @params - http request params
* */
public String makeServiceCall(String url, int method,
List<NameValuePair> params) {
try {
// http client
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpEntity httpEntity = null;
HttpResponse httpResponse = null;
// Checking http request method type
if (method == POST) {
HttpPost httpPost = new HttpPost(url);
// adding post params
if (params != null) {
httpPost.setEntity(new UrlEncodedFormEntity(params));
}
httpResponse = httpClient.execute(httpPost);
} else if (method == GET) {
// appending params to url
if (params != null) {
String paramString = URLEncodedUtils
.format(params, "utf-8");
url += "?" + paramString;
}
HttpGet httpGet = new HttpGet(url);
httpResponse = httpClient.execute(httpGet);
}
httpEntity = httpResponse.getEntity();
response = EntityUtils.toString(httpEntity);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return response;
}
public class HospitalList_Activity extends ListActivity {
private ProgressDialog pDialog;
// URL to get Hospitals JSON
private static String url = "http://14.140.200.186/hospital/get_hospital.php";
// JSON Node names
private static final String TAG_HOSPITAL = "Hospitals";
//private static final String TAG_ID = "id";
private static final String TAG_NAME = "hospital_name";
// Hospitals JSONArray
JSONArray Hospitals = null;
// Hashmap for ListView
ArrayList<HashMap<String, String>> hospitallist;
//ArrayList<String> citylist;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_hospital_list_);
ListView listView=getListView();
hospitallist = new ArrayList<HashMap<String, String>>();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Intent in = new Intent(getApplicationContext(), Specialities_Activity.class);
startActivity(in);
}
});
new GetHospitals().execute();
}
/**
* Async task class to get json by making HTTP call
* */
private class GetHospitals extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
pDialog = new ProgressDialog(HospitalList_Activity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected Void doInBackground(Void... arg0) {
// Creating service handler class instance
ServiceHandler sh = new ServiceHandler();
// Making a request to url and getting response
String jsonStr = sh.makeServiceCall(url, ServiceHandler.GET);
Log.d("Response: ", "> " + jsonStr);
if (jsonStr != null) {
try {
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
Hospitals = jsonObj.getJSONArray(TAG_HOSPITAL);
// looping through All Cities
for (int i = 0; i < Hospitals.length(); i++) {
JSONObject c = Hospitals.getJSONObject(i);
//String id = c.getString(TAG_ID);
String name = c.getString(TAG_NAME);
HashMap<String, String> Hospitals = new HashMap<String, String>();
Hospitals.put(TAG_NAME, name);
// adding contact to Cities list
hospitallist.add(Hospitals);
}
} catch (JSONException e) {
e.printStackTrace();
}
} else {
Log.e("ServiceHandler", "Couldn't get any data from the url");
}
return null;
}
@Override
protected void onPostExecute(Void result)
{
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
/**`enter code here`
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(HospitalList_Activity.this, hospitallist, R.layout.hospital_list_item, new String[] { TAG_NAME}, new int[] { R.id.name});
setListAdapter(adapter);
}
}
答案 0 :(得分：2)
公共类CityNameActivity扩展了ListActivity {
ListView list;
Map <String, String> cityListWithId = new HashMap<String, String>();
private ProgressDialog pDialog;
// URL to get Cities JSON
private static String url = "http://14.140.200.186/Hospital/get_city.php";
// JSON Node names
private static final String TAG_CITIES = "Cities";
private static final String TAG_ID = "city_id";
private static final String TAG_NAME = "city_name";
// Cities JSONArray
JSONArray Cities = null;
// Hashmap for ListView
ArrayList<HashMap<String, String>> citylist;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.cityname_activity_main);
ListView listView=getListView();
citylist = new ArrayList<HashMap<String, String>>();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
//String tagname = ((TextView) findViewById(R.id.name)).getText().toString();
Map<String, String> tempHashmap = (Map<String, String>) parent.getItemAtPosition(position);
String tagName = tempHashmap.get(TAG_NAME);
System.out.println("tagname" + tagName);
String tagId = (String)cityListWithId.get(tagName);
System.out.println("tagId" + tagId);
Toast.makeText(CityNameActivity.this, tagId,Toast.LENGTH_SHORT).show();
}
});
new GetCities().execute();
}
/**
* Async task class to get json by making HTTP call
* */
private class GetCities extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
pDialog = new ProgressDialog(CityNameActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected Void doInBackground(Void... arg0) {
// Creating service handler class instance
ServiceHandler sh = new ServiceHandler();
// Making a request to url and getting response
String jsonStr = sh.makeServiceCall(url, ServiceHandler.GET);
Log.d("Response: ", "> " + jsonStr);
if (jsonStr != null) {
try {
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
Cities = jsonObj.getJSONArray(TAG_CITIES);
// looping through All Cities
for (int i = 0; i < Cities.length(); i++) {
JSONObject c = Cities.getJSONObject(i);
//String id = c.getString(TAG_ID);
String name = c.getString(TAG_NAME);
cityListWithId.put(c.getString(TAG_NAME), c.getString(TAG_ID));
HashMap<String, String> Cities = new HashMap<String, String>();
Cities.put(TAG_NAME, name);
// adding contact to Cities list
citylist.add(Cities);
}
} catch (JSONException e) {
e.printStackTrace();
}
} else {
Log.e("ServiceHandler", "Couldn't get any data from the url");
}
return null;
}
@Override
protected void onPostExecute(Void result)
{
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
/**`enter code here`
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(CityNameActivity.this, citylist, R.layout.city_list_item, new String[] { TAG_NAME}, new int[] { R.id.name});
setListAdapter(adapter);
}
}
}
答案 1 :(得分：0)
在processing time方法上，您可以添加此项以获取产品的ID。
ItemClick()答案 2 :(得分：0)
为什么每次都要点击这项服务。根据我的意见，不要在onItemClick上调用服务。当您启动活动或应用程序启动异步任务并将数据传递到列表视图时。
请找到以下代码。我只是重构一些事情，所以如果有什么不对的话请让我
public class CityNameActivity extends ListActivity
{
private ProgressDialog pDialog;
// URL to get Cities JSON
private static String url = "http://14.140.200.186/Hospital/get_city.php";
// JSON Node names
private static final String TAG_CITIES = "Cities";
//private static final String TAG_ID = "id";
private static final String TAG_NAME = "city_name";
// Cities JSONArray
JSONArray Cities = null;
// Hashmap for ListView
ArrayList<HashMap<String, String>> citylist;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
new GetCities().execute();
ListView listView=getListView();
citylist = new ArrayList<HashMap<String, String>>();
// list.setOnClickListener(this);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
if(citylist!=null && !citylist.isEmpty())
{
Toast.makeText(CityNameActivity.this,""+citylist.get(position).get(TAG_NAME).toString(),Toast.LENGTH_SHORT).show();
}
}
});
new GetCities().execute();
}
private class GetCities extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
pDialog = new ProgressDialog(CityNameActivity.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected Void doInBackground(Void... arg0) {
// Creating service handler class instance
ServiceHandler sh = new ServiceHandler();
// Making a request to url and getting response
String jsonStr = sh.makeServiceCall(url, ServiceHandler.GET);
Log.d("Response: ", "> " + jsonStr);
if (jsonStr != null) {
try {
JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
Cities = jsonObj.getJSONArray(TAG_CITIES);
// looping through All Cities
for (int i = 0; i < Cities.length(); i++) {
JSONObject c = Cities.getJSONObject(i);
//String id = c.getString(TAG_ID);
String name = c.getString(TAG_NAME);
HashMap<String, String> Cities = new HashMap<String, String>();
Cities.put(TAG_NAME, name);
// adding contact to Cities list
citylist.add(Cities);
}
} catch (JSONException e) {
e.printStackTrace();
}
} else {
Log.e("ServiceHandler", "Couldn't get any data from the url");
}
return null;
}
@Override
protected void onPostExecute(Void result)
{
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
/**`enter code here`
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(CityNameActivity.this, citylist, R.layout.city_list_item, new String[] { TAG_NAME}, new int[] { R.id.name});
setListAdapter(adapter);
}
}
}