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我決定允許progressDialog正常運行，但我故意切斷我的數據計劃（但我的WIFI和3G打開），以便應用程序認爲網絡可用，我需要用戶獲得一個消息通過Toast之後或asynctask完成運行後告訴他們存在連接困難。目前發生的事情是，當的AsyncTask完成運行時並沒有實際的互聯網服務中，progressDialog駁回和應用程序崩潰在AsyncTask期間的網絡丟失
好，我添加的代碼，讓我改一下這個問題：
我需要基本上只是通過Toast或通過Toast進行的活動，就像當您嘗試登錄您的Twitter或Facebook應用程序並且網絡不穩定或緩慢時一樣，過了一段時間對話框進度對話框消失後，您會收到一條消息網絡有一些困難。這與檢查手機上是否存在WI-FI或移動連接不同（我已經處理過）。這種情況時模擬是在連接過程中，但連接速度慢，或者不相符，或者你有沒有數據計劃認購
下面是該活動的代碼：
package com.insidetown;
import java.util.ArrayList;
import android.os.AsyncTask;
import java.util.HashMap;
import java.util.List;
import org.apache.http.NameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ListActivity;
import android.app.ProgressDialog;
import android.content.DialogInterface;
import android.content.DialogInterface.OnDismissListener;
import android.content.Intent;
import android.os.Bundle;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.Spinner;
import android.widget.Toast;
public class Result extends ListActivity {
//final String category = ((Spinner) findViewById(R.id.spinner1)).getSelectedItem().toString();
//final String location = ((Spinner) findViewById(R.id.spinner2)).getSelectedItem().toString();
String category = "Flowers";
String location = "Washington";
// Progress Dialog
private ProgressDialog pDialog;
//private static final int LONG_DELAY = 7500; // 3.5 seconds
// Creating JSON Parser object
JSONParser jParser = new JSONParser();
ArrayList<HashMap<String, String>> productsList;
// url to get all products list
private String url_all_products = "http://theURL.com.ng/123.php?category="+category+"&location="+location;
category="+category+"&location="+location;
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_PRODUCTS = "data";
private static final String TAG_NAME = "name";
private static final String TAG_ADDRESS = "address";
private static final String TAG_PHONE = "phone";
// products JSONArray
JSONArray products = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.result);
// Hashmap for ListView
productsList = new ArrayList<HashMap<String, String>>();
// Loading results in Background Thread
new LoadAllProducts().execute();
// Get listview
//ListView lv = getListView();
}
/**
* Background Async Task to Load all product by making HTTP Request
* */
class LoadAllProducts extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = ProgressDialog.show(
Result.this,
null,
"loading...",
true,
true,
new DialogInterface.OnCancelListener(){
@Override
public void onCancel(DialogInterface dialog) {
Toast.makeText(Result.this,
"Operation Cancelled.",
Toast.LENGTH_LONG).show();
// cancel the AsyncTask here!
LoadAllProducts.this.cancel(true);
}
}
);
}
/**
* getting results from url
* */
protected String doInBackground(String... args) {
if(pDialog != null && pDialog.isShowing()){
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url_all_products, "GET", params);
// Check your log cat for JSON reponse
//Log.d("Results: ", json.toString());
try {
// Checking for SUCCESS TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// results returned
// Getting Array of results
products = json.getJSONArray(TAG_PRODUCTS);
// looping through results
for (int i = 0; i < products.length(); i++) {
JSONObject c = products.getJSONObject(i);
// Storing each json item in variable
String name = c.getString(TAG_NAME);
String address = c.getString(TAG_ADDRESS);
String phone = c.getString(TAG_PHONE);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_NAME, name);
map.put(TAG_ADDRESS, address);
map.put(TAG_PHONE, phone);
// adding HashList to ArrayList
productsList.add(map);
}
}
else {
Toast.makeText(getApplicationContext(), "oops! There seems to be a problem", 3).show();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog after getting results
pDialog.dismiss();
// updating UI from Background Thread
runOnUiThread(new Runnable() {
public void run() {
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(
Result.this, productsList,
R.layout.list_item, new String[] { TAG_NAME,
TAG_ADDRESS, TAG_PHONE},
new int[] { R.id.name, R.id.address, R.id.phone });
// updating listview
setListAdapter(adapter);
}
});
}
}
}
@懶忍者和@克里斯因爲onPostExecute是主UI線程上運行
05-08 09:56:25.180: I/Choreographer(872): Skipped 65 frames! The application may be doing too much work on its main thread.
05-08 09:56:26.470: D/dalvikvm(872): GC_FOR_ALLOC freed 35K, 3% free 3611K/3716K, paused 131ms, total 140ms
05-08 09:56:27.530: I/Choreographer(872): Skipped 121 frames! The application may be doing too much work on its main thread.
05-08 09:56:28.800: W/System.err(872): java.net.UnknownHostException: Unable to resolve host "insidetown.com.ng": No address associated with hostname
05-08 09:56:28.860: W/System.err(872): at java.net.InetAddress.lookupHostByName(InetAddress.java:424)
05-08 09:56:28.860: W/System.err(872): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
05-08 09:56:28.860: W/System.err(872): at java.net.InetAddress.getAllByName(InetAddress.java:214)
05-08 09:56:28.860: W/System.err(872): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
05-08 09:56:28.860: W/System.err(872): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
05-08 09:56:28.870: W/System.err(872): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
05-08 09:56:28.870: W/System.err(872): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
05-08 09:56:28.870: W/System.err(872): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
05-08 09:56:28.870: W/System.err(872): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
05-08 09:56:28.890: W/System.err(872): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
05-08 09:56:28.890: W/System.err(872): at com.insidetown.JSONParser.makeHttpRequest(JSONParser.java:67)
05-08 09:56:28.910: W/System.err(872): at com.insidetown.Result$LoadAllProducts.doInBackground(Result.java:118)
05-08 09:56:28.910: W/System.err(872): at com.insidetown.Result$LoadAllProducts.doInBackground(Result.java:1)
05-08 09:56:28.910: W/System.err(872): at android.os.AsyncTask$2.call(AsyncTask.java:288)
05-08 09:56:28.950: W/System.err(872): at java.util.concurrent.FutureTask.run(FutureTask.java:237)
05-08 09:56:28.950: W/System.err(872): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
05-08 09:56:28.950: W/System.err(872): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
05-08 09:56:29.000: W/System.err(872): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
05-08 09:56:29.000: W/System.err(872): at java.lang.Thread.run(Thread.java:841)
05-08 09:56:29.030: W/System.err(872): Caused by: libcore.io.GaiException: getaddrinfo failed: EAI_NODATA (No address associated with hostname)
05-08 09:56:29.040: W/System.err(872): at libcore.io.Posix.getaddrinfo(Native Method)
05-08 09:56:29.040: W/System.err(872): at libcore.io.ForwardingOs.getaddrinfo(ForwardingOs.java:61)
05-08 09:56:29.040: W/System.err(872): at java.net.InetAddress.lookupHostByName(InetAddress.java:405)
05-08 09:56:29.070: W/System.err(872): ... 18 more
05-08 09:56:29.070: E/Buffer Error(872): Error converting result java.lang.NullPointerException: lock == null
05-08 09:56:29.100: E/JSON Parser(872): Error parsing data org.json.JSONException: End of input at character 0 of
05-08 09:56:29.100: W/dalvikvm(872): threadid=11: thread exiting with uncaught exception (group=0xb4a59b90)
05-08 09:56:29.220: E/AndroidRuntime(872): FATAL EXCEPTION: AsyncTask #1
05-08 09:56:29.220: E/AndroidRuntime(872): Process: com.insidetown, PID: 872
05-08 09:56:29.220: E/AndroidRuntime(872): java.lang.RuntimeException: An error occured while executing doInBackground()
05-08 09:56:29.220: E/AndroidRuntime(872): at android.os.AsyncTask$3.done(AsyncTask.java:300)
05-08 09:56:29.220: E/AndroidRuntime(872): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
05-08 09:56:29.220: E/AndroidRuntime(872): at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
05-08 09:56:29.220: E/AndroidRuntime(872): at java.util.concurrent.FutureTask.run(FutureTask.java:242)
05-08 09:56:29.220: E/AndroidRuntime(872): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
05-08 09:56:29.220: E/AndroidRuntime(872): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
05-08 09:56:29.220: E/AndroidRuntime(872): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
05-08 09:56:29.220: E/AndroidRuntime(872): at java.lang.Thread.run(Thread.java:841)
05-08 09:56:29.220: E/AndroidRuntime(872): Caused by: java.lang.NullPointerException
05-08 09:56:29.220: E/AndroidRuntime(872): at com.insidetown.Result$LoadAllProducts.doInBackground(Result.java:127)
05-08 09:56:29.220: E/AndroidRuntime(872): at com.insidetown.Result$LoadAllProducts.doInBackground(Result.java:1)
05-08 09:56:29.220: E/AndroidRuntime(872): at android.os.AsyncTask$2.call(AsyncTask.java:288)
05-08 09:56:29.220: E/AndroidRuntime(872): at java.util.concurrent.FutureTask.run(FutureTask.java:237)
05-08 09:56:29.220: E/AndroidRuntime(872): ... 4 more
05-08 09:56:29.260: I/Choreographer(872): Skipped 1072 frames! The application may be doing too much work on its main thread.
05-08 09:56:30.040: I/Choreographer(872): Skipped 471 frames! The application may be doing too much work on its main thread.
05-08 09:56:31.550: I/Choreographer(872): Skipped 606 frames! The application may be doing too much work on its main thread.
05-08 09:56:31.680: I/Choreographer(872): Skipped 82 frames! The application may be doing too much work on its main thread.
05-08 09:56:33.870: E/WindowManager(872): android.view.WindowLeaked: Activity com.insidetown.Result has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b4df2280 V.E..... R.....ID 0,0-304,96} that was originally added here
05-08 09:56:33.870: E/WindowManager(872): at android.view.ViewRootImpl.<init>(ViewRootImpl.java:346)
05-08 09:56:33.870: E/WindowManager(872): at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:248)
05-08 09:56:33.870: E/WindowManager(872): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
05-08 09:56:33.870: E/WindowManager(872): at android.app.Dialog.show(Dialog.java:286)
05-08 09:56:33.870: E/WindowManager(872): at android.app.ProgressDialog.show(ProgressDialog.java:116)
05-08 09:56:33.870: E/WindowManager(872): at com.insidetown.Result$LoadAllProducts.onPreExecute(Result.java:88)
05-08 09:56:33.870: E/WindowManager(872): at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
05-08 09:56:33.870: E/WindowManager(872): at android.os.AsyncTask.execute(AsyncTask.java:535)
05-08 09:56:33.870: E/WindowManager(872): at com.insidetown.Result.onCreate(Result.java:67)
05-08 09:56:33.870: E/WindowManager(872): at android.app.Activity.performCreate(Activity.java:5243)
05-08 09:56:33.870: E/WindowManager(872): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
05-08 09:56:33.870: E/WindowManager(872): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2140)
05-08 09:56:33.870: E/WindowManager(872): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2226)
05-08 09:56:33.870: E/WindowManager(872): at android.app.ActivityThread.access$700(ActivityThread.java:135)
05-08 09:56:33.870: E/WindowManager(872): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1397)
05-08 09:56:33.870: E/WindowManager(872): at android.os.Handler.dispatchMessage(Handler.java:102)
05-08 09:56:33.870: E/WindowManager(872): at android.os.Looper.loop(Looper.java:137)
05-08 09:56:33.870: E/WindowManager(872): at android.app.ActivityThread.main(ActivityThread.java:4998)
05-08 09:56:33.870: E/WindowManager(872): at java.lang.reflect.Method.invokeNative(Native Method)
05-08 09:56:33.870: E/WindowManager(872): at java.lang.reflect.Method.invoke(Method.java:515)
05-08 09:56:33.870: E/WindowManager(872): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777)
05-08 09:56:33.870: E/WindowManager(872): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593)
05-08 09:56:33.870: E/WindowManager(872): at dalvik.system.NativeStart.main(Native Method)
05-08 09:56:33.870: I/Choreographer(872): Skipped 809 frames! The application may be doing too much work on its main thread.
05-08 09:56:34.130: I/Choreographer(872): Skipped 162 frames! The application may be doing too much work on its main thread.
05-08 09:56:35.740: I/Process(872): Sending signal. PID: 872 SIG: 9
您應該嘗試添加最少的代碼片段來展示您遇到的問題。 – JeffS
我已經添加了代碼，請看看。基本上我需要的僅僅是應用程序的響應，就像當您嘗試登錄您的Twitter或Facebook應用程序並且網絡不穩定或緩慢時一樣，過了一會兒對話框進度對話框消失並且您收到消息說網絡是有一些困難。這與檢查手機上是否存在WI-FI或移動連接不同（我已經處理過）。模擬的情況是連接速度慢或不一致，或者您沒有訂閱數據計劃 – user3591264
設置一個計時器，如果網絡操作完成，則取消它。如果網絡操作不成功，計時器將觸發，您可以顯示錯誤消息並取消或忽略異步任務。 –