我有一个类CDealListing，我从那里执行AsynkTask类，这是一个单独的类，我想要的是在AsynkTask类onPost方法上更新类CDealListing的UI。请帮助我......
这是我的课程CDealListing的代码
public class CDealAppListing extends Fragment {
public static String m_DealListingURL = "http://192.166.0.110:8080/ireward/rest/json/metallica/getDealListInJSON";
public static String s_szresult = " ";
public static RecyclerView m_RecyclerView;
public static CDealAppListingAdapter m_oAdapter;
public static CDealAppDatastorage item;
public ArrayList<CDealAppDatastorage> s_oDataset;
public int[] m_n_FormImage;
public View m_Main;
public CRegistrationSessionManagement m_oSessionManagement;
public String m_szMobileNumber, m_szEncryptedPassword;
public LinearLayoutManager mLayoutManager;
public AppCompatButton m_showMore;
public ProgressBar mProgressBar;
public int m_n_DefaultRecordCount = 5;// intiallly record count is 5.
public int m_n_DeafalutLastCount = 0;//initally lastcount is 0.
public String sz_RecordCount, sz_LastCount;
//declare boolean
private CJsonsResponse m_oJsonsResponse;
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
m_Main = inflater.inflate(R.layout.deal_app_listing, container, false);//intialize mainLayout
new CDealDataSent().execute(m_DealListingURL);
init();//initialize method
implementScroll();
return m_Main;
}
public void init() {
mProgressBar = (ProgressBar) m_Main.findViewById(R.id.progressBar1);
mProgressBar.setVisibility(View.GONE);
m_showMore = (AppCompatButton) m_Main.findViewById(R.id.show_more);
m_showMore.setBackgroundColor(Color.TRANSPARENT);
m_showMore.setVisibility(View.GONE);
// Getting the string array from strings.xml
m_n_FormImage = new int[]{
R.drawable.amazon,
R.drawable.whatsapp,
R.drawable.zorpia,
R.drawable.path,
R.drawable.app_me,
R.drawable.evernote,
R.drawable.app_me};
m_RecyclerView = (RecyclerView) m_Main.findViewById(R.id.my_recycler_view);//finding id of recyclerview
m_RecyclerView.setItemAnimator(new DefaultItemAnimator());//setting default animation to recyclerview
m_RecyclerView.setHasFixedSize(true);//fixing size of recyclerview
mLayoutManager = new LinearLayoutManager(getActivity());
m_RecyclerView.setLayoutManager(mLayoutManager);//showing odata vertically to user.
m_oSessionManagement = new CRegistrationSessionManagement(getActivity());
HashMap<String, String> user = m_oSessionManagement.getRegistrationDetails();
m_szEncryptedPassword = user.get(m_oSessionManagement.s_szKEY_PASSWORD);
m_szMobileNumber = user.get(m_oSessionManagement.s_szKEY_MOBILENUMBER);
sz_RecordCount = String.valueOf(m_n_DefaultRecordCount);// increment of record count
sz_LastCount = String.valueOf(m_n_DeafalutLastCount);
}
public void implementScroll() {
m_RecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
if (newState == RecyclerView.SCROLL_STATE_IDLE){
}
}
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
if (dy > 0) {
m_showMore.setVisibility(View.VISIBLE);
m_showMore.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//change boolean value
m_showMore.setVisibility(View.GONE);
m_n_DefaultRecordCount = m_n_DefaultRecordCount + 5;
m_n_DeafalutLastCount = m_n_DeafalutLastCount + 5;
sz_RecordCount = String.valueOf(m_n_DefaultRecordCount);
sz_LastCount = String.valueOf(m_n_DeafalutLastCount);
new DealNext().execute(m_DealListingURL);
}
});
} else {
m_showMore.setVisibility(View.GONE);
}
}
});
}
//sending deal data to retreive response from server
public String DealListing(String url, CRegistrationDataStorage login) {
InputStream inputStream = null;
m_oJsonsResponse = new CJsonsResponse();
try {
// 1. create HttpClient
HttpClient httpclient = new DefaultHttpClient();
// 2. make POST request to the given URL
HttpPost httpPost = new HttpPost(url);
String json = "";
// 3. build jsonObject
JSONObject jsonObject = new JSONObject();
jsonObject.put("agentCode", m_szMobileNumber);
jsonObject.put("pin", m_szEncryptedPassword);
jsonObject.put("recordcount", sz_RecordCount);
jsonObject.put("lastcountvalue", sz_LastCount);
//jsonObject.put("emailId", "nirajk1190@gmail.com");
// 4. convert JSONObject to JSON to String
json = jsonObject.toString();
// 5. set json to StringEntity
StringEntity se = new StringEntity(json);
// 6. set httpPost Entity
httpPost.setEntity(se);
// 7. Set some headers to inform server about the type of the content
httpPost.setHeader("Content-type", "application/json");
// 8. Execute POST request to the given URL
HttpResponse httpResponse = httpclient.execute(httpPost);
HttpEntity entity = httpResponse.getEntity();
// 9. receive response as inputStream
inputStream = entity.getContent();
System.out.println("InputStream....:" + inputStream.toString());
System.out.println("Response....:" + httpResponse.toString());
StatusLine statusLine = httpResponse.getStatusLine();
System.out.println("statusLine......:" + statusLine.toString());
////Log.d("resp_body", resp_body.toString());
int statusCode = statusLine.getStatusCode();
// 10. convert inputstream to string
if (statusCode == 200) {
// 10. convert inputstream to string
if (inputStream != null)
s_szresult = m_oJsonsResponse.convertInputStreamToString(inputStream);
//String resp_body =
EntityUtils.toString(httpResponse.getEntity());
} else
s_szresult = "Did not work!";
} catch (Exception e) {
Log.d("InputStream", e.getLocalizedMessage());
}
System.out.println("resul.....:" + s_szresult);
// 11. return s_szResult
return s_szresult;
}
这是我的AsynkTask类
/ sending deal data to server and retreive response......
class CDealDataSent extends AsyncTask<String, Void, String> {
public JSONObject m_oResponseobject;
public ProgressDialog m_PDialog;
public CRegistrationDataStorage oRegisterStorage;
public CDealAppDatastorage item;
// @Override
protected void onPreExecute() {
super.onPreExecute();
m_PDialog = new ProgressDialog(getActivity());
m_PDialog.setMessage("Please wait while Loading Deals...");
m_PDialog.setCancelable(false);
m_PDialog.show();
}
@Override
protected String doInBackground(String... urls) {
return DealListing(urls[0], oRegisterStorage);// sending data to server...
}
// onPostExecute displays the results of the AsyncTask.
@Override
protected void onPostExecute(String result) {
m_PDialog.dismiss();
try {
m_oResponseobject = new JSONObject(result);// getting response from server
final JSONArray posts = m_oResponseobject.optJSONArray("dealList");
s_oDataset = new ArrayList<CDealAppDatastorage>();
for (int i = 0; i < posts.length(); i++) {
JSONObject post = posts.getJSONObject(i);
item = new CDealAppDatastorage();
item.setM_szHeaderText(post.getString("dealname"));
item.setM_szsubHeaderText(post.getString("dealcode"));
item.setM_n_Image(m_n_FormImage[i]);
s_oDataset.add(item);
}
getResponse();
} catch (JSONException e) {
e.printStackTrace();
}
}
public void getResponse() throws JSONException {
if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Transaction Successful")) {
m_oAdapter = new CDealAppListingAdapter(s_oDataset);//creating object of adapter and addd setting odata to adapter for use.
m_RecyclerView.setAdapter(m_oAdapter);//adding adapter to recyclerview
} else if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Connection Not Available")) {
Toast.makeText(getActivity(), "Connection not avaliable", Toast.LENGTH_SHORT).show();
}else if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Deal List Not Found")){
Toast.makeText(getActivity(),"No More Deals",Toast.LENGTH_SHORT).show();
}
System.out.println("agentCode...." + m_szMobileNumber);
System.out.println("password...." + m_szEncryptedPassword);
System.out.println("record////" + sz_RecordCount);
System.out.println("last:........" + sz_LastCount);
}
}
在asynkTask类中获取类CDealListing的响应方法更新UI
答案 0 :(得分：0)
有三种方式
Fragment onPostExecute()的某些方法
BroadcastReceiver onPostExecute()
Fragment。答案 1 :(得分：0)
一种方法是声明一个监听器接口，并将该接口的实例（或者可能是一个Runnable）传递给AsyncTask的构造函数。
在您的片段代码中：
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
...
new CDealDataSent(new Runnable() {
@Override
public void run() {
// perform update UI code here
}
}).execute(m_DealListingURL);
...
}
在AsyncTask代码中：
class CDealDataSent extends AsyncTask<String, Void, String> {
private final Runnable mOnPostExecuteRunnable;
CDealDataSent(Runnable onPostExecuteRunnable) {
mOnPostExecuteRunnable = onPostExecuteRunnable;
}
...
@Override
protected void onPostExecute(String result) {
...
if (mPostExecuteRunnable != null) {
mPostExecuteRunnable.run();
}
...
}
}
您还可以使用片段中的AsyncTask的匿名子类并覆盖onPostExecute（）：
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
...
new CDealDataSent() {
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result); // be sure to call super first to do normal processing
... // update your UI here
}
}.execute(m_DealListingURL);
...
}
请注意，如果您不小心，这两个解决方案都容易出现Activity / Fragment泄漏，因为Runnable / anonymous子类的父类被保留为隐式引用。如果用户退出onDestroy（）中的活动，请务必取消任何未完成的AsyncTasks。
您可以通过静态嵌套类来缓解任何潜在的泄漏问题，或者可以将Handler实例传递给AsyncTask，以便在onPostExecute（）完成其工作时发送消息。有关此问题的讨论，请参阅What's the correct way to implement AsyncTask? static or non static nested class?。