在列表视图与AsyncTask的显示数据 [英] Show data in listview with Asynctask
本文介绍了在列表视图与AsyncTask的显示数据的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我的成功显示列表视图,从Web服务的JSON我的数据,但我想补充Asyntask .. 在那里我可以把code Asyntask在我的code ..
I success show my data from web service JSON in listview, but i want to add Asyntask.. Where i can put code Asyntask in my code..
这是我的code,显示在列表视图中的数据
public class Jadwal_remix extends ListActivity {
String v_date;
JSONArray r_js = null;
ArrayList<HashMap<String, String>> myArray = new ArrayList<HashMap<String,String>>();
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.main);
String status ="";
String date = "";
String result = "";
String url = "http://10.0.2.2/remix/view_list.php";
JSONParser jParser = new JSONParser();
JSONObject json = jParser.AmbilJson(url);
try
{
r_js = json.getJSONArray("view_list");
for (int i =0; i < r_js.length(); i++)
{
String my_array = "";
JSONObject ar = r_js.getJSONObject(i);
status = ar.getString("st");
date = ar.getString("date");
result = ar.getString("result");
if (status.trim().equals("er"))
{
my_array += "Sorry "+result;
HashMap<String, String> map = new HashMap<String, String>();
map.put("result", my_array);
myArray.add(map);
}
else
{
my_array += "Date : "+date+" "+"Result : "+result;
HashMap<String, String> map = new HashMap<String, String>();
map.put("result", my_array);
myArray.add(map);
}
}
}
catch (JSONException e)
{
e.printStackTrace();
}
adapter_listview();
}
public void adapter_listview() {
ListAdapter adapter = new SimpleAdapter(this, jadwalRemix,R.layout.my_list,new String[] { "result"}, new int[] {R.id.txtResult});
setListAdapter(adapter);
}
}
这JSONParser
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
public JSONObject AmbilJson(String url) {
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}
请帮我,在那里我可以把$ C $下Asyntask .. 非常感谢。
Please help me, where i can put code for Asyntask.. Thanks a lot..
确定,我得到的样品code,我的code现在这个样子
public class Jadwal_remix extends ListActivity {
String v_date;
JSONArray r_js = null;
ArrayList<HashMap<String, String>> myArray = new ArrayList<HashMap<String,String>>();
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.main);
private class myProses extends AsyncTask<Void, Void, Void> {
ProgressDialog dialog;
protected void onPreExecute() {
dialog = ProgressDialog.show(Jadwal_remix.this, "", "Loading... Please wait", true);
}
protected Void doInBackground(Void... params) {
String status ="";
String date = "";
String result = "";
String url = "http://10.0.2.2/remix/view_list.php";
JSONParser jParser = new JSONParser();
JSONObject json = jParser.AmbilJson(url);
try
{
r_js = json.getJSONArray("view_list");
for (int i =0; i < r_js.length(); i++)
{
String my_array = "";
JSONObject ar = r_js.getJSONObject(i);
status = ar.getString("st");
date = ar.getString("date");
result = ar.getString("result");
if (status.trim().equals("er"))
{
my_array += "Sorry "+result;
HashMap<String, String> map = new HashMap<String, String>();
map.put("result", my_array);
myArray.add(map);
}
else
{
my_array += "Date : "+date+" "+"Result : "+result;
HashMap<String, String> map = new HashMap<String, String>();
map.put("result", my_array);
myArray.add(map);
}
}
}
catch (JSONException e)
{
e.printStackTrace();
}
return null;
protected void onPostExecute(Void unused) {
adapter_listview();
dialog.dismiss();
}
}
public void adapter_listview() {
ListAdapter adapter = new SimpleAdapter(this, jadwalRemix,R.layout.my_list,new String[] { "result"}, new int[] {R.id.txtResult});
setListAdapter(adapter);
}
}
当服务器死亡
林获取问题,但仍然加载.. 我怎么能显示的信息如:无法连接到服务器??
Im get problem when server is die, it still loading.. how i can show message ex : can't connect to server..??
推荐答案
这是我的code,请尝试这一个,
This is my code please try this one,
MAinActivity.java
MAinActivity.java
public class MyActivity extends Activity {
private ListView contests_listView;
private ProgressBar pgb;
ActivitiesBean bean;
ArrayList<Object> listActivities;
ActivityAdapter adapter;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_listview);
contests_listView = (ListView) findViewById(R.id.activity_listView);
pgb = (ProgressBar) findViewById(R.id.contests_progressBar);
listActivities = new ArrayList<Object>();
new FetchActivitesTask().execute();
}
public class FetchActivitesTask extends AsyncTask<Void, Void, Void> {
int i =0;
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
pgb.setVisibility(View.VISIBLE);
}
@Override
protected Void doInBackground(Void... params) {
// TODO Auto-generated method stub
String url = "Your URL Here";
String strResponse = util.makeWebCall(url);
try {
JSONObject objResponse = new JSONObject(strResponse);
JSONArray jsonnodes = objResponse.getJSONArray(nodes);
for (i = 0; i < jsonnodes.length(); i++)
{
String str = Integer.toString(i);
Log.i("Value of i",str);
JSONObject jsonnode = jsonnodes.getJSONObject(i);
JSONObject jsonnodevalue = jsonnode.getJSONObject(node);
bean = new ActivitiesBean();
bean.title = jsonnodevalue.getString(title);
bean.image = jsonnodevalue.getString(field_activity_image_fid);
listActivities.add(bean);
}
}
catch (JSONException e) {
e.printStackTrace();
}
return null;
}
@Override
public void onPostExecute(Void result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
pgb.setVisibility(View.GONE);
displayAdapter();
}
}
public void displayAdapter()
{
adapter = new ActivityAdapter(this, listActivities);
contests_listView.setAdapter(adapter);
contests_listView.setOnItemClickListener(new OnItemClickListener() {
//@Override
public void onItemClick(AdapterView<?> arg0, View arg1,
int position, long id) {
// your onclick Activity
}
});
}
}
util.class
util.class
public static String makeWebCall(String url) {
DefaultHttpClient client = new DefaultHttpClient();
HttpGet httpRequest = new HttpGet(url);
// HttpPost post = new HttpPost(url);
try {
HttpResponse httpResponse = client.execute(httpRequest);
final int statusCode = httpResponse.getStatusLine().getStatusCode();
if (statusCode != HttpStatus.SC_OK) {
return null;
}
HttpEntity entity = httpResponse.getEntity();
InputStream instream = null;
if (entity != null) {
instream = entity.getContent();
}
return iStream_to_String(instream);
}
catch (IOException e) {
httpRequest.abort();
// Log.w(getClass().getSimpleName(), "Error for URL =>" + url, e);
}
return null;
}
public static String iStream_to_String(InputStream is1) {
BufferedReader rd = new BufferedReader(new InputStreamReader(is1), 4096);
String line;
StringBuilder sb = new StringBuilder();
try {
while ((line = rd.readLine()) != null) {
sb.append(line);
}
rd.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String contentOfMyInputStream = sb.toString();
return contentOfMyInputStream;
}
}
ActivityBean.java
ActivityBean.java
public class ActivitiesBean implements Serializable{
/**
*
*/
private static final long serialVersionUID = 1L;
public String title;
public String image;
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getImage() {
return image;
}
public void setImage(String image) {
this.image = image;
}
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