这是我做的简单的Android项目。跑步时我没有收到任何警告或错误。但是ListView没有填充。我不明白出了什么问题。
因为我没有＆＃39;了解确切问题的位置并复制粘贴所有代码都没有帮助，这是我的项目代码库：https://bitbucket.org/geejo/msk-v2
任何形式的帮助将不胜感激
MSKFragment.java
public class MSKFragment extends android.support.v4.app.Fragment implements android.support.v4.app.LoaderManager.LoaderCallbacks<Cursor>
{
private ServiceAdapter mServiceAdapter;
public static final int SERVICE_LOADER = 0;
private static final String[] SERVICE_COLUMNS =
{
ServiceContract.ServiceEntry.TABLE_NAME,
ServiceContract.ServiceEntry._ID,
ServiceContract.ServiceEntry.COLUMN_NAME,
ServiceContract.ServiceEntry.COLUMN_ORGANIZATION_NAME,
ServiceContract.ServiceEntry.COLUMN_PRICE
};
public static final int COL_ID = 0;
public static final int COL_NAME = 1;
public static final int COL_ORG_NAME = 2;
public static final int COL_PRICE = 3;
public MSKFragment()
{
}
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
getLoaderManager().initLoader(SERVICE_LOADER, null, this);
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater)
{
inflater.inflate(R.menu.menu_fragment_msk, menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item)
{
int id = item.getItemId();
if (id == R.id.action_refresh)
{
//Moving functions to a helper class, so that when Activity starts the data can be displayed
updateServices();
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
mServiceAdapter = new ServiceAdapter(getActivity(), null, 0);
View rootView = inflater.inflate(R.layout.fragment_msk, container, false);
ListView listView = (ListView) rootView.findViewById(R.id.listViewMainService);
listView.setAdapter(mServiceAdapter);
return rootView;
}
@Override
public void onStart()
{
super.onStart();
//Refresh called and service updated when activity starts
updateServices();
}
//Calling FetchServiceTask and executing it.
private void updateServices()
{
FetchServicesTask serviceTask = new FetchServicesTask(getActivity());
serviceTask.execute();
}
@Override
public android.support.v4.content.Loader<Cursor> onCreateLoader(int i, Bundle args)
{
Uri serviceUri = ServiceContract.ServiceEntry.buildServiceUri(i);
return new android.support.v4.content.CursorLoader(getActivity(), serviceUri, null, null, null, null);
}
@Override
public void onLoadFinished(android.support.v4.content.Loader<Cursor> loader, Cursor data)
{
mServiceAdapter.swapCursor(data);
}
@Override
public void onLoaderReset(android.support.v4.content.Loader<Cursor> loader)
{
mServiceAdapter.swapCursor(null);
}
}
FetchServices.java （AsyncTasks）
public class FetchServicesTask extends AsyncTask<String, Void, Void>
{
private final String LOG_TAG = FetchServicesTask.class.getSimpleName();
private final Context mContext;
private boolean DEBUG = true;
public FetchServicesTask(Context context )
{
mContext = context;
}
private String[] getServicesDatafromJson(String serviceJsonStr) throws JSONException
{
final String MSK_NAME = "name";
final String MSK_PRICE = "price";
final String MSK_ORG_NAME = "organizationName";
final String MSK_POSTED_USER = "postedUser";
final String MSK_PROFILE = "profile";
int totalResults = 25;
String resultStrs[] = new String[totalResults];
try
{
JSONArray serviceArray = new JSONArray(serviceJsonStr);
Vector<ContentValues> cVVector = new Vector<ContentValues>(serviceArray.length());
for(int i=0;i<serviceArray.length();i++)
{
String name, organizationName;
int price;
JSONObject serviceObject = serviceArray.getJSONObject(i);
name = serviceObject.getString(MSK_NAME);
price = serviceObject.getInt(MSK_PRICE);
JSONObject postedUserObject = serviceObject.getJSONObject(MSK_POSTED_USER);
JSONObject profileObject = postedUserObject.getJSONObject(MSK_PROFILE);
organizationName = profileObject.getString(MSK_ORG_NAME);
ContentValues serviceValues = new ContentValues();
serviceValues.put(ServiceContract.ServiceEntry.COLUMN_NAME, name);
serviceValues.put(ServiceContract.ServiceEntry.COLUMN_ORGANIZATION_NAME, organizationName);
serviceValues.put(ServiceContract.ServiceEntry.COLUMN_PRICE, price);
cVVector.add(serviceValues);
}
int inserted = 0;
if(cVVector.size()>0)
{
ContentValues[] cvArray = new ContentValues[cVVector.size()];
cVVector.toArray(cvArray);
inserted = mContext.getContentResolver().bulkInsert(ServiceContract.ServiceEntry.CONTENT_URI, cvArray);
}
Log.d(LOG_TAG, "FetchServicesTask Complete. " + inserted + " Inserted");
}
catch(JSONException e)
{
Log.e(LOG_TAG, e.getMessage(), e);
e.printStackTrace();
}
return null;
}
/////////////////////////////// NETWORKING BOILER PLATE ///////////////////////////
@Override
protected Void doInBackground(String... params)
{
if (params.length == 0)
{
return null;
}
HttpURLConnection urlConnection = null; //Streaming data using HTTP
String serviceJsonStr = null; //raw JSON response
BufferedReader reader = null; //read text from character i/p stream
int pageNo = 1;
int numResults = 5;
try
{
//-------------------------CONNECTION--------------------//
final String SERVICE_BASE_URL = "http://myservicekart.com/public/";
final String SEARCH_BASE_URL = "http://myservicekart.com/public/search?";
final String SEARCH_PARAM = "search";
final String PAGE_PARAM = "pageno";
/*Using a helper class UriBuilder for building and manipulating URI references*/
Uri builtServiceUri = Uri.parse(SERVICE_BASE_URL);
Uri builtSearchUri = Uri.parse(SEARCH_BASE_URL).buildUpon().
appendQueryParameter(SEARCH_PARAM, "").
appendQueryParameter(PAGE_PARAM, Integer.toString(pageNo)).
build();
URL searchUrl = new URL(builtSearchUri.toString());
Log.v(LOG_TAG, "Built SearchUri" +builtSearchUri.toString());
urlConnection = (HttpURLConnection) searchUrl.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
//------------------------BUFFERING---------------------//
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if(inputStream==null)
{
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line = null;
while((line = reader.readLine()) != null)
{
buffer.append(line + "\n");
}
if(buffer.length()==0)
{
return null;
}
serviceJsonStr = buffer.toString();
getServicesDatafromJson(serviceJsonStr);
Log.v(LOG_TAG, "Services JSON String: " +serviceJsonStr);
}
catch(IOException e)
{
Log.e(LOG_TAG, "Error cannot connect to URL", e);
return null;
}
catch (JSONException e)
{
e.printStackTrace();
}
finally
{
if(urlConnection!=null)
{
urlConnection.disconnect();
}
if(reader!=null)
{
try
{
reader.close();
}
catch (final IOException e)
{
Log.e(LOG_TAG,"Error closing stream",e);
}
}
}
return null;
}
}
ServiceAdapter.java
public class ServiceAdapter extends CursorAdapter
{
public ServiceAdapter(Context context, Cursor c, int flags)
{
super(context, c, flags);
}
private String convertCursorRowToUXFormat(Cursor cursor)
{
return cursor.getString(MSKFragment.COL_NAME) + "-" + cursor.getString(MSKFragment.COL_ORG_NAME) +
" - " + cursor.getInt(MSKFragment.COL_PRICE);
}
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent)
{
View view = LayoutInflater.from(context).inflate(R.layout.list_item_main, parent, false);
return view;
}
@Override
public void bindView(View view, Context context, Cursor cursor)
{
TextView tv = (TextView)view;
tv.setText(convertCursorRowToUXFormat(cursor));
}
}
答案 0 :(得分：0)
将 ServiceAdapter.java 中的方法 newView（）更改为：
public View newView(Context context, Cursor cursor, ViewGroup parent){
View view = LayoutInflater.from(context).inflate(android.R.layout.simple_list_item_1, parent, false);
return view;}