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POCreate ListAdapter from a JSON
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copied!<p>I'm getting some problem in an Android APP: I want to read info from a Feed RSS and present them in some android view. I'm using the <code>android-async-http1.4.3.jar</code> libs to connect my APP to this site: <a href="http://ajax.googleapis.com/ajax/services/feed/load?v=1.0&num=10&q=http://f1grandprix.motorionline.com/feed/" rel="nofollow">http://ajax.googleapis.com/ajax/services/feed/load?v=1.0&num=10&q=http://f1grandprix.motorionline.com/feed/</a></p> <p>With this connection I'm downloading the XML file and I'm transforming it into a JSON file with gson libs, but when i try the APP to my Android Phone I'm getting a Null Pointer Exception. The class to connect, to get the xml and to transform it into JSON code is the following: </p> <pre><code> private void loadTitle() { String URL = "http://ajax.googleapis.com/ajax/services/feed/load?v=1.0&num=10&q=http://f1grandprix.motorionline.com/feed/"; AsyncHttpClient client = new AsyncHttpClient(); client.get(URL, new AsyncHttpResponseHandler() { @Override public void onSuccess(String text) { super.onSuccess(text); Gson decoder = new Gson(); JsonResponse jr = decoder.fromJson(text, JsonResponse.class); Entry[] entries = jr.responseData.feed.entries; for (int i = 0; i < entries.length; i++) { Log.d("NET", "Il titolo della " + i + " entry è: " + entries[i].title); } final ListView lv_title = (ListView) findViewById(R.id.lv_title); //ListAdapter la_title = new TitleAdapter(MainActivity.this, entries); //Log.d("LIST_ADAPTER", "Caricato correttamente il list adaptor: "+ la_title); //lv_title.setAdapter(la_title); lv_title.setAdapter(new TitleAdapter(MainActivity.this, entries)); pleaseWait.hide(); } @Override public void onFailure(Throwable arg0, String arg1) { super.onFailure(arg0, arg1); Log.d("FAIL", "Failure"); pleaseWait.hide(); } }); } </code></pre> <p>The TitleAdapter.java is the following:</p> <pre><code>public class TitleAdapter extends ArrayAdapter<Entry> { public TitleAdapter(Context context, Entry[] title) { super(context, R.layout.list_item, R.id.lv_title, title); } </code></pre> <p>}</p> <p>And finally I'm getting this error:</p> <pre><code>02-23 12:46:05.525: E/AndroidRuntime(4577): FATAL EXCEPTION: main 02-23 12:46:05.525: E/AndroidRuntime(4577): java.lang.NullPointerException 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:355) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.ArrayAdapter.getView(ArrayAdapter.java:323) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.AbsListView.obtainView(AbsListView.java:1495) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.ListView.measureHeightOfChildren(ListView.java:1216) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.ListView.onMeasure(ListView.java:1127) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.view.View.measure(View.java:8335) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.RelativeLayout.measureChild(RelativeLayout.java:566) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:381) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.view.View.measure(View.java:8335) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.view.View.measure(View.java:8335) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.LinearLayout.measureVertical(LinearLayout.java:531) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.view.View.measure(View.java:8335) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.view.View.measure(View.java:8335) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.view.ViewRoot.performTraversals(ViewRoot.java:843) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.view.ViewRoot.handleMessage(ViewRoot.java:1892) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.os.Handler.dispatchMessage(Handler.java:99) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.os.Looper.loop(Looper.java:130) 02-23 12:46:05.525: E/AndroidRuntime(4577): at android.app.ActivityThread.main(ActivityThread.java:3835) 02-23 12:46:05.525: E/AndroidRuntime(4577): at java.lang.reflect.Method.invokeNative(Native Method) 02-23 12:46:05.525: E/AndroidRuntime(4577): at java.lang.reflect.Method.invoke(Method.java:507) 02-23 12:46:05.525: E/AndroidRuntime(4577): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:864) 02-23 12:46:05.525: E/AndroidRuntime(4577): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:622) 02-23 12:46:05.525: E/AndroidRuntime(4577): at dalvik.system.NativeStart.main(Native Method) </code></pre> <p>Can someone help me to fix this problem? Thank you!</p>

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