我正在尝试填充listview，但模拟器中没有显示任何错误。
这是我的MainActivity
public class MainActivity extends ListActivity {
// Progress Dialog
private ProgressDialog pDialog;
// Creating JSON Parser object
JSONParser jParser = new JSONParser();
ArrayList<HashMap<String, String>> productsList;
// url to get all products list
private static String url_all_products = "http://10.0.2.2/callarocket/get_all.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_PRODUCTS = "products";
private static final String TAG_PID = "pid";
private static final String TAG_NAME = "name";
// products JSONArray
JSONArray products = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Hashmap for ListView
productsList = new ArrayList<HashMap<String, String>>();
// Loading products in Background Thread
new LoadAllProducts().execute();
// Get listview
ListView lv = getListView();
// on seleting single product
// launching Edit Product Screen
// lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
//
// @Override
// public void onItemClick(AdapterView<?> parent, View view,
// int position, long id) {
// // getting values from selected ListItem
// String pid = ((TextView) view.findViewById(R.id.pid)).getText()
// .toString();
//
// // Starting new intent
// Intent in = new Intent(getApplicationContext(),
// EditProductActivity.class);
// // sending pid to next activity
// in.putExtra(TAG_PID, pid);
//
// // starting new activity and expecting some response back
// startActivityForResult(in, 100);
// }
// });
}
// Response from Edit Product Activity
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// super.onActivityResult(requestCode, resultCode, data);
// // if result code 100
// if (resultCode == 100) {
// // if result code 100 is received
// // means user edited/deleted product
// // reload this screen again
// Intent intent = getIntent();
// finish();
// startActivity(intent);
// }
}
/**
* 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 = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Loading requests. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
/**
* getting All products from url
* */
protected String doInBackground(String... args) {
// 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("All Requests: ", json.toString());
try {
// Checking for SUCCESS TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// products found
// Getting Array of Products
products = json.getJSONArray(TAG_PRODUCTS);
// looping through All Products
for (int i = 0; i < products.length(); i++) {
JSONObject c = products.getJSONObject(i);
// Storing each json item in variable
String id = c.getString(TAG_PID);
String name = c.getString(TAG_NAME);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_PID, id);
map.put(TAG_NAME, name);
// adding HashList to ArrayList
productsList.add(map);
}
} else {
// no products found
// Launch Add New product Activity
// Intent i = new Intent(getApplicationContext(),
// NewProductActivity.class);
// // Closing all previous activities
// i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
// startActivity(i);
}
} 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 all products
pDialog.dismiss();
// updating UI from Background Thread
runOnUiThread(new Runnable() {
public void run() {
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(
MainActivity.this, productsList,
R.layout.single_list, new String[] { TAG_PID,
TAG_NAME},
new int[] { R.id.jid, R.id.name });
// updating listview
setListAdapter(adapter);
}
});
}
}
}
这是我的ListView
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<!-- Main ListView
Always give id value as list(@android:id/list)
-->
<ListView
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
这是我的single_list.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<!-- Product id (pid) - will be HIDDEN - used to pass to other activity -->
<TextView
android:id="@+id/jid"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="gone" />
<!-- Name Label -->
<TextView
android:id="@+id/name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingTop="6dip"
android:paddingLeft="6dip"
android:textSize="17dip"
android:textStyle="bold" />
</LinearLayout>
这是logcat
02-27 04:09:28.998 2954-2974/com.example.user.rocket W/System.err﹕ org.json.JSONException: No value for products
02-27 04:09:28.998 2954-2974/com.example.user.rocket W/System.err﹕ at org.json.JSONObject.get(JSONObject.java:389)
02-27 04:09:28.998 2954-2974/com.example.user.rocket W/System.err﹕ at org.json.JSONObject.getJSONArray(JSONObject.java:584)
02-27 04:09:28.998 2954-2974/com.example.user.rocket W/System.err﹕ at com.example.user.rocket.MainActivity$LoadAllProducts.doInBackground(MainActivity.java:143)
02-27 04:09:28.998 2954-2974/com.example.user.rocket W/System.err﹕ at com.example.user.rocket.MainActivity$LoadAllProducts.doInBackground(MainActivity.java:109)
02-27 04:09:28.998 2954-2974/com.example.user.rocket W/System.err﹕ at android.os.AsyncTask$2.call(AsyncTask.java:288)
02-27 04:09:28.998 2954-2974/com.example.user.rocket W/System.err﹕ at java.util.concurrent.FutureTask.run(FutureTask.java:237)
02-27 04:09:28.998 2954-2974/com.example.user.rocket W/System.err﹕ at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
02-27 04:09:28.998 2954-2974/com.example.user.rocket W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
02-27 04:09:28.998 2954-2974/com.example.user.rocket W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
02-27 04:09:28.999 2954-2974/com.example.user.rocket W/System.err﹕ at java.lang.Thread.run(Thread.java:818)
我正在尝试使用JSONParser从MySQL数据库填充listview。该应用程序能够运行，但模拟器中没有显示任何数据。我试过谷歌搜索这个错误org.json.JSONException: No value for products，但我找不到任何可以解决这个问题的解决方案。