我想從 PHP MySQL 中檢索一個數據，然後傳到試圖列表中。我使用的下面的代碼，但是還是沒把數據放到 List View 中，如何改這個問題。
貼出我的代碼，大家看看是哪兒出錯了。
Activity Codes
public class View extends Activity{
// Progress Dialog
// 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://atlantis-us.com/viewFile.php";
// JSON Node names
private static final String TAG_NAME = "name";
ListView lv;
// products JSONArray
JSONArray products = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.all_products);
// Get listview
lv = (ListView) findViewById(R.id.list);
// Hashmap for ListView
productsList = new ArrayList<HashMap<String, String>>();
new LoadAllProducts().execute();
}
class LoadAllProducts extends AsyncTask<String, String, String> {
@Override
protected String doInBackground(String... arg0) {
// TODO Auto-generated method stub
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
JSONObject json = jParser.makeHttpRequest(url_all_products, "GET", params);
Log.d("All Products: ", json.toString());
ListAdapter adapter = new SimpleAdapter(
View.this, productsList,
R.layout.list_item, new String[] {
TAG_NAME},
new int[] {R.id.name });
// updating listview
lv.setAdapter(adapter);
return null;
}
}
}
JSONParser Class
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
// function get json from url
// by making HTTP POST or GET mehtod
public JSONObject makeHttpRequest(String url, String method,
List<NameValuePair> params) {
// Making HTTP request
try {
// check for request method
if(method == "POST"){
// request method is POST
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}else if(method == "GET"){
// request method is GET
DefaultHttpClient httpClient = new DefaultHttpClient();
String paramString = URLEncodedUtils.format(params, "utf-8");
url += "?" + paramString;
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
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;
}
}
log cat
10-26 14:57:53.673: I/Choreographer(1391): Skipped 61 frames! The application may be doing too much work on its main thread.
10-26 14:57:54.653: D/All Products:(1391): {"products":[{"name":"Ghalia"},{"name":"yuan"},{"name":"kevin"},{"name":"kevin"},{"name":"kevin"},{"name":"Ghalia"},{"name":"Ghalia"},{"name":"dbgg"},{"name":"Ghalia"},{"name":"Ghalia"},{"name":"test"}]}
10-26 14:57:54.663: W/dalvikvm(1391): threadid=11: thread exiting with uncaught exception (group=0x40a13300)
10-26 14:57:54.684: E/AndroidRuntime(1391): FATAL EXCEPTION: AsyncTask #1
10-26 14:57:54.684: E/AndroidRuntime(1391): java.lang.RuntimeException: An error occured while executing doInBackground()
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.os.AsyncTask$3.done(AsyncTask.java:299)
10-26 14:57:54.684: E/AndroidRuntime(1391): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
10-26 14:57:54.684: E/AndroidRuntime(1391): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
10-26 14:57:54.684: E/AndroidRuntime(1391): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
10-26 14:57:54.684: E/AndroidRuntime(1391): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
10-26 14:57:54.684: E/AndroidRuntime(1391): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
10-26 14:57:54.684: E/AndroidRuntime(1391): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
10-26 14:57:54.684: E/AndroidRuntime(1391): at java.lang.Thread.run(Thread.java:856)
10-26 14:57:54.684: E/AndroidRuntime(1391): Caused by: android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:4607)
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.view.ViewRootImpl.requestLayout(ViewRootImpl.java:835)
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.view.View.requestLayout(View.java:15129)
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.view.View.requestLayout(View.java:15129)
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.view.View.requestLayout(View.java:15129)
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.view.View.requestLayout(View.java:15129)
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.view.View.requestLayout(View.java:15129)
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.widget.AbsListView.requestLayout(AbsListView.java:1928)
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.widget.ListView.setAdapter(ListView.java:488)
10-26 14:57:54.684: E/AndroidRuntime(1391): at com.example.mysql.View$LoadAllProducts.doInBackground(View.java:74)
10-26 14:57:54.684: E/AndroidRuntime(1391): at com.example.mysql.View$LoadAllProducts.doInBackground(View.java:1)
10-26 14:57:54.684: E/AndroidRuntime(1391): at android.os.AsyncTask$2.call(AsyncTask.java:287)
10-26 14:57:54.684: E/AndroidRuntime(1391): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
10-26 14:57:54.684: E/AndroidRuntime(1391): ... 5 more
在 doInBackground()中，你不能對任何試圖直接執行更新操作，你在 doInBackground()這裡出錯了，所以在 onPostExecute()裡面添加下面的代碼：
ListAdapter adapter = new SimpleAdapter(
View.this, productsList,
R.layout.list_item, new String[] {
TAG_NAME},
new int[] {R.id.name });
// updating listview
lv.setAdapter(adapter);
