刚刚在这里和其他地方找到了很多在 Android 上使用 PHP 进行 JSON 解析的示例，并尝试在我的项目中使用。在Activity中是可以的，但是换成Fragment就不行了。我认为我犯了一个愚蠢的错误。
fragment 代码:
package com.example.waitersoriginal;
import java.util.ArrayList;
import java.util.HashMap;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.ListFragment;
import android.app.ProgressDialog;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
public class ListaFragment extends ListFragment {
private ProgressDialog pDialog;
private static final String URL_SELECT ="http://localhost/waiters/select_bebidas.php";
//JSONTAGS
private static final String TAG_NOME = "NOME";
private static final String TAG_BEBIDAS = "bebidas";
private static final String TAG_DESCR = "DESCR";
private JSONArray mProdutos = null;
private ArrayList<HashMap<String, String>> mProdutosList;
public ListaFragment(){}
@Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
return inflater.inflate(R.layout.lista_fragment, container, false);
}
@Override
public void onResume() {
// TODO Auto-generated method stub
super.onResume();
//loading the comments via AsyncTask
new LoadEvents().execute();
}
public void updateJSONdata() {
mProdutosList = new ArrayList<HashMap<String, String>>();
JSONParser jParser = new JSONParser();
JSONObject json = jParser.getJSONFromUrl(URL_SELECT);
try {
mProdutos = json.getJSONArray(TAG_BEBIDAS);
for (int i = 0; i < mProdutos.length(); i++) {
JSONObject c = mProdutos.getJSONObject(i);
String nome = c.getString(TAG_NOME);
String descr = c.getString(TAG_DESCR);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
map.put(TAG_NOME, nome);
map.put(TAG_DESCR, descr);
mProdutosList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
private void updateList() {
ListAdapter adapter = new SimpleAdapter(getActivity(), mProdutosList,
R.layout.list_item,
new String[] { TAG_NOME, TAG_DESCR},
new int[] { R.id.pid, R.id.name});
setListAdapter(adapter);
ListView lv = getListView();
lv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
}
});
}
public class LoadEvents extends AsyncTask<Void, Void, Boolean> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(getActivity());
pDialog.setMessage("Loading Events...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
@Override
protected Boolean doInBackground(Void... arg0) {
updateJSONdata();
return null;
}
@Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
pDialog.dismiss();
updateList();
}
}
}
Logcat 错误:
10-22 22:41:40.814: E/AndroidRuntime(2513): FATAL EXCEPTION: main
10-22 22:41:40.814: E/AndroidRuntime(2513): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.waitersoriginal/com.example.waitersoriginal.BebidaActivity}: android.view.InflateException: Binary XML file line #15: Error inflating class fragment
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.ActivityThread.access$600(ActivityThread.java:141)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.os.Handler.dispatchMessage(Handler.java:99)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.os.Looper.loop(Looper.java:137)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.ActivityThread.main(ActivityThread.java:5103)
10-22 22:41:40.814: E/AndroidRuntime(2513): at java.lang.reflect.Method.invokeNative(Native Method)
10-22 22:41:40.814: E/AndroidRuntime(2513): at java.lang.reflect.Method.invoke(Method.java:525)
10-22 22:41:40.814: E/AndroidRuntime(2513): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
10-22 22:41:40.814: E/AndroidRuntime(2513): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
10-22 22:41:40.814: E/AndroidRuntime(2513): at dalvik.system.NativeStart.main(Native Method)
10-22 22:41:40.814: E/AndroidRuntime(2513): Caused by: android.view.InflateException: Binary XML file line #15: Error inflating class fragment
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:713)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.view.LayoutInflater.rInflate(LayoutInflater.java:755)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.view.LayoutInflater.inflate(LayoutInflater.java:492)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.view.LayoutInflater.inflate(LayoutInflater.java:397)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.view.LayoutInflater.inflate(LayoutInflater.java:353)
10-22 22:41:40.814: E/AndroidRuntime(2513): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:267)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.Activity.setContentView(Activity.java:1895)
10-22 22:41:40.814: E/AndroidRuntime(2513): at com.example.waitersoriginal.BebidaActivity.onCreate(BebidaActivity.java:19)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.Activity.performCreate(Activity.java:5133)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
10-22 22:41:40.814: E/AndroidRuntime(2513): ... 11 more
10-22 22:41:40.814: E/AndroidRuntime(2513): Caused by: java.lang.RuntimeException: Content has view with id attribute 'android.R.id.list' that is not a ListView class
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.ListFragment.ensureList(ListFragment.java:402)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.ListFragment.onViewCreated(ListFragment.java:203)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:866)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1035)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.FragmentManagerImpl.addFragment(FragmentManager.java:1137)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.app.Activity.onCreateView(Activity.java:4746)
10-22 22:41:40.814: E/AndroidRuntime(2513): at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:689)
10-22 22:41:40.814: E/AndroidRuntime(2513): ... 21 more
有什么想法吗？
谢谢大家。
编辑:
lista_fragment.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ListView
android:id="@+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
编辑2:
Logcat 错误:
10-22 23:46:11.842: W/System.err(2729): org.apache.http.conn.HttpHostConnectException: Connection to http://localhost refused
10-22 23:46:12.062: W/System.err(2729): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:183)
10-22 23:46:12.192: W/System.err(2729): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
10-22 23:46:12.212: W/System.err(2729): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
10-22 23:46:12.262: W/System.err(2729): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
10-22 23:46:12.292: W/System.err(2729): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
10-22 23:46:12.342: W/System.err(2729): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
10-22 23:46:12.352: W/System.err(2729): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
10-22 23:46:12.362: W/System.err(2729): at com.example.waitersoriginal.JSONParser.getJSONFromUrl(JSONParser.java:30)
10-22 23:46:12.362: W/System.err(2729): at com.example.waitersoriginal.ListaFragment.updateJSONdata(ListaFragment.java:60)
10-22 23:46:12.392: W/System.err(2729): at com.example.waitersoriginal.ListaFragment$LoadEvents.doInBackground(ListaFragment.java:122)
10-22 23:46:12.392: W/System.err(2729): at com.example.waitersoriginal.ListaFragment$LoadEvents.doInBackground(ListaFragment.java:1)
10-22 23:46:12.412: W/System.err(2729): at android.os.AsyncTask$2.call(AsyncTask.java:287)
10-22 23:46:12.422: W/System.err(2729): at java.util.concurrent.FutureTask.run(FutureTask.java:234)
10-22 23:46:12.442: W/System.err(2729): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
10-22 23:46:12.462: W/System.err(2729): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
10-22 23:46:12.462: W/System.err(2729): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
10-22 23:46:12.472: W/System.err(2729): at java.lang.Thread.run(Thread.java:841)
10-22 23:46:12.492: W/System.err(2729): Caused by: java.net.ConnectException: failed to connect to /127.0.0.1 (port 80): connect failed: ECONNREFUSED (Connection refused)
10-22 23:46:12.512: W/System.err(2729): at libcore.io.IoBridge.connect(IoBridge.java:114)
10-22 23:46:12.512: W/System.err(2729): at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
10-22 23:46:12.512: W/System.err(2729): at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459)
10-22 23:46:12.552: W/System.err(2729): at java.net.Socket.connect(Socket.java:842)
10-22 23:46:12.562: W/System.err(2729): at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:119)
10-22 23:46:12.562: W/System.err(2729): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:144)
10-22 23:46:12.562: W/System.err(2729): ... 16 more
10-22 23:46:12.562: W/System.err(2729): Caused by: libcore.io.ErrnoException: connect failed: ECONNREFUSED (Connection refused)
10-22 23:46:12.592: W/System.err(2729): at libcore.io.Posix.connect(Native Method)
10-22 23:46:12.652: W/System.err(2729): at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:85)
10-22 23:46:12.652: W/System.err(2729): at libcore.io.IoBridge.connectErrno(IoBridge.java:127)
10-22 23:46:12.662: W/System.err(2729): at libcore.io.IoBridge.connect(IoBridge.java:112)
10-22 23:46:12.662: W/System.err(2729): ... 21 more
10-22 23:46:12.662: E/Buffer Error(2729): Error converting result java.lang.NullPointerException: lock == null
10-22 23:46:12.702: E/JSON Parser(2729): Error parsing data org.json.JSONException: End of input at character 0 of
10-22 23:46:12.702: W/dalvikvm(2729): threadid=11: thread exiting with uncaught exception (group=0xb2f30648)
10-22 23:46:12.712: E/AndroidRuntime(2729): FATAL EXCEPTION: AsyncTask #1
10-22 23:46:12.712: E/AndroidRuntime(2729): java.lang.RuntimeException: An error occured while executing doInBackground()
10-22 23:46:12.712: E/AndroidRuntime(2729): at android.os.AsyncTask$3.done(AsyncTask.java:299)
10-22 23:46:12.712: E/AndroidRuntime(2729): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
10-22 23:46:12.712: E/AndroidRuntime(2729): at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
10-22 23:46:12.712: E/AndroidRuntime(2729): at java.util.concurrent.FutureTask.run(FutureTask.java:239)
10-22 23:46:12.712: E/AndroidRuntime(2729): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
10-22 23:46:12.712: E/AndroidRuntime(2729): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
10-22 23:46:12.712: E/AndroidRuntime(2729): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
10-22 23:46:12.712: E/AndroidRuntime(2729): at java.lang.Thread.run(Thread.java:841)
10-22 23:46:12.712: E/AndroidRuntime(2729): Caused by: java.lang.NullPointerException
10-22 23:46:12.712: E/AndroidRuntime(2729): at com.example.waitersoriginal.ListaFragment.updateJSONdata(ListaFragment.java:65)
10-22 23:46:12.712: E/AndroidRuntime(2729): at com.example.waitersoriginal.ListaFragment$LoadEvents.doInBackground(ListaFragment.java:122)
10-22 23:46:12.712: E/AndroidRuntime(2729): at com.example.waitersoriginal.ListaFragment$LoadEvents.doInBackground(ListaFragment.java:1)
10-22 23:46:12.712: E/AndroidRuntime(2729): at android.os.AsyncTask$2.call(AsyncTask.java:287)
10-22 23:46:12.712: E/AndroidRuntime(2729): at java.util.concurrent.FutureTask.run(FutureTask.java:234)
10-22 23:46:12.712: E/AndroidRuntime(2729): ... 4 more
10-22 23:46:13.412: W/EGL_emulation(2729): eglSurfaceAttrib not implemented
10-22 23:46:14.142: E/WindowManager(2729): Activity com.example.waitersoriginal.BebidaActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b320ffd0 V.E..... R......D 0,0-576,96} that was originally added here
10-22 23:46:14.142: E/WindowManager(2729): android.view.WindowLeaked: Activity com.example.waitersoriginal.BebidaActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b320ffd0 V.E..... R......D 0,0-576,96} that was originally added here
10-22 23:46:14.142: E/WindowManager(2729): at android.view.ViewRootImpl.<init>(ViewRootImpl.java:345)
10-22 23:46:14.142: E/WindowManager(2729): at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:239)
10-22 23:46:14.142: E/WindowManager(2729): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.Dialog.show(Dialog.java:281)
10-22 23:46:14.142: E/WindowManager(2729): at com.example.waitersoriginal.ListaFragment$LoadEvents.onPreExecute(ListaFragment.java:117)
10-22 23:46:14.142: E/WindowManager(2729): at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
10-22 23:46:14.142: E/WindowManager(2729): at android.os.AsyncTask.execute(AsyncTask.java:534)
10-22 23:46:14.142: E/WindowManager(2729): at com.example.waitersoriginal.ListaFragment.onResume(ListaFragment.java:50)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.Fragment.performResume(Fragment.java:1738)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:919)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1057)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1039)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.FragmentManagerImpl.dispatchResume(FragmentManager.java:1850)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.Activity.performResume(Activity.java:5221)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2780)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:2819)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2266)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.ActivityThread.access$600(ActivityThread.java:141)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
10-22 23:46:14.142: E/WindowManager(2729): at android.os.Handler.dispatchMessage(Handler.java:99)
10-22 23:46:14.142: E/WindowManager(2729): at android.os.Looper.loop(Looper.java:137)
10-22 23:46:14.142: E/WindowManager(2729): at android.app.ActivityThread.main(ActivityThread.java:5103)
10-22 23:46:14.142: E/WindowManager(2729): at java.lang.reflect.Method.invokeNative(Native Method)
10-22 23:46:14.142: E/WindowManager(2729): at java.lang.reflect.Method.invoke(Method.java:525)
10-22 23:46:14.142: E/WindowManager(2729): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
10-22 23:46:14.142: E/WindowManager(2729): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
10-22 23:46:14.142: E/WindowManager(2729): at dalvik.system.NativeStart.main(Native Method)
最佳答案
你已经提到你的类是ListFragment，这意味着你的xml应该只有一个listview，而你里面有一个LinearLayout和一个ListView。你的 xml 应该是这样的......
<ListView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/listview"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
如果您不想更改 xml，请将类更改为 Fragment
public class ListaFragment extends Fragment
手动查找 ListView
ListView listView;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState){
ctx=getActivity();
LayoutInflater m_inflater = LayoutInflater.from(getActivity());
rootView = m_inflater.inflate(R.layout.lista_fragment, null);
listView=rootView.findViewById(R.id.listView1);
return rootView;
}
然后从那里拿走它。
关于android - 尝试从 Fragment 解析 Listview 中的 JSON 文件，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/26520590/