我的问题：
我有一个称为控制台活动的片段活动，它位于h3海盗页面的视图寻呼机中。当我只是查看页面时它会正常加载，但随后我快速浏览页面，我收到了这个错误。
12-07 20:14:39.851: E/AndroidRuntime(24498): FATAL EXCEPTION: main
12-07 20:14:39.851: E/AndroidRuntime(24498): java.lang.NullPointerException
12-07 20:14:39.851: E/AndroidRuntime(24498): at trade.ly.tradely.ConsoleActivity$RemoteDataTask.onPostExecute(ConsoleActivity.java:145)
12-07 20:14:39.851: E/AndroidRuntime(24498): at trade.ly.tradely.ConsoleActivity$RemoteDataTask.onPostExecute(ConsoleActivity.java:1)
12-07 20:14:39.851: E/AndroidRuntime(24498): at android.os.AsyncTask.finish(AsyncTask.java:631)
12-07 20:14:39.851: E/AndroidRuntime(24498): at android.os.AsyncTask.access$600(AsyncTask.java:177)
12-07 20:14:39.851: E/AndroidRuntime(24498): at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:644)
12-07 20:14:39.851: E/AndroidRuntime(24498): at android.os.Handler.dispatchMessage(Handler.java:99)
12-07 20:14:39.851: E/AndroidRuntime(24498): at android.os.Looper.loop(Looper.java:137)
12-07 20:14:39.851: E/AndroidRuntime(24498): at android.app.ActivityThread.main(ActivityThread.java:5039)
12-07 20:14:39.851: E/AndroidRuntime(24498): at java.lang.reflect.Method.invokeNative(Native Method)
12-07 20:14:39.851: E/AndroidRuntime(24498): at java.lang.reflect.Method.invoke(Method.java:511)
12-07 20:14:39.851: E/AndroidRuntime(24498): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
12-07 20:14:39.851: E/AndroidRuntime(24498): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
12-07 20:14:39.851: E/AndroidRuntime(24498): at dalvik.system.NativeStart.main(Native Method)
以下是我的控制台活动的代码。
public class ConsoleActivity extends SherlockFragment {
private ProfilePictureView userProfilePictureView;
private TextView userNameView;
private TextView userLocationView;
ListView listview;
List<ParseObject> ob;
ListViewAdapter adapter;
private List<UserPosts> userpostarraylist = null;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.activity_console, container, false);
userProfilePictureView = (ProfilePictureView) v.findViewById(R.id.userProfilePicture);
userNameView = (TextView) v.findViewById(R.id.userName);
userLocationView = (TextView) v.findViewById(R.id.userLocation);
SlidingLayer slidingLayer = (SlidingLayer) v.findViewById(R.id.slidingLayer1);
slidingLayer.setShadowWidthRes(R.dimen.shadow_width);
slidingLayer.setOffsetWidth(70);
slidingLayer.setShadowDrawable(R.drawable.sidebar_shadow);
slidingLayer.setStickTo(SlidingLayer.STICK_TO_RIGHT);
slidingLayer.setCloseOnTapEnabled(true);
Button newPage = (Button)v.findViewById(R.id.post_button);
newPage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(getActivity(), PostActivity.class);
startActivity(intent);
}
});
Button logoutButton = (Button) v.findViewById(R.id.logout_button);
logoutButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
onLogoutButtonClicked();
}
});
// Fetch Facebook user info if the session is active
Session session = ParseFacebookUtils.getSession();
if (session != null && session.isOpened()) {
makeMeRequest();
}
return v;
}
private class RemoteDataTask extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
}
protected Void doInBackground(Void... params) {
// Create the array
userpostarraylist = new ArrayList<UserPosts>();
try {
ParseQuery<ParseObject> query = new ParseQuery<ParseObject>("testData");
// Restrict to cases where the author is the current user.
query.whereEqualTo("author", ParseUser.getCurrentUser());
query.orderByDescending("createdAt");
ob = query.find();
for (ParseObject country : ob) {
ParseFile image = (ParseFile) country.get("Photo");
UserPosts upost = new UserPosts();
upost.setPrice((String) country.get("Price"));
upost.setDescription((String) country.get("Description"));
upost.setCategory((String) country.get("MainCat"));
upost.setSubCategory((String) country.get("SubCat"));
upost.setEmail((String) country.get("PEmail"));
upost.setName((String) country.get("PName"));
upost.setPNumber((String) country.get("PPhone"));
upost.setMeet((String) country.get("PMeet"));
upost.setPrice((String) country.get("Price"));
upost.setTitle((String) country.get("Title"));
upost.setId((String) country.getObjectId());
upost.setPhone(image.getUrl());
userpostarraylist.add(upost);
}
} catch (ParseException e) {
Log.e("Error", e.getMessage());
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(Void result) {
listview = (ListView) getActivity().findViewById(R.id.userpostlistview);
adapter = new ListViewAdapter(getActivity (), userpostarraylist);
listview.setAdapter(adapter);
}
}
@Override
public void onResume() {
super.onResume();
ParseUser currentUser = ParseUser.getCurrentUser();
if (currentUser != null) {
// Check if the user is currently logged
// and show any cached content
updateViewsWithProfileInfo();
//try this to kill the errors!!!
//new RemoteDataTask().execute();
} else {
// If the user is not logged in, go to the
// activity showing the login view.
startLoginActivity();
}
}
private void makeMeRequest() {
Request request = Request.newMeRequest(ParseFacebookUtils.getSession(),
new Request.GraphUserCallback() {
@Override
public void onCompleted(GraphUser user, Response response) {
if (user != null) {
// Create a JSON object to hold the profile info
JSONObject userProfile = new JSONObject();
try {
// Populate the JSON object
userProfile.put("facebookId", user.getId());
userProfile.put("name", user.getName());
if (user.getLocation().getProperty("name") != null) {
userProfile.put("location", (String) user
.getLocation().getProperty("name"));
}
// Save the user profile info in a user property
ParseUser currentUser = ParseUser
.getCurrentUser();
currentUser.put("profile", userProfile);
currentUser.saveInBackground();
// Show the user info
updateViewsWithProfileInfo();
} catch (JSONException e) {
Log.d(TradelyApplication.TAG,
"Error parsing returned user data.");
}
} else if (response.getError() != null) {
if ((response.getError().getCategory() == FacebookRequestError.Category.AUTHENTICATION_RETRY)
|| (response.getError().getCategory() == FacebookRequestError.Category.AUTHENTICATION_REOPEN_SESSION)) {
Log.d(TradelyApplication.TAG,
"The facebook session was invalidated.");
onLogoutButtonClicked();
} else {
Log.d(TradelyApplication.TAG,
"Some other error: "
+ response.getError()
.getErrorMessage());
}
}
}
});
request.executeAsync();
}
private void updateViewsWithProfileInfo() {
ParseUser currentUser = ParseUser.getCurrentUser();
if (currentUser.get("profile") != null) {
JSONObject userProfile = currentUser.getJSONObject("profile");
try {
if (userProfile.getString("facebookId") != null) {
String facebookId = userProfile.get("facebookId")
.toString();
userProfilePictureView.setProfileId(facebookId);
} else {
// Show the default, blank user profile picture
userProfilePictureView.setProfileId(null);
}
if (userProfile.getString("name") != null) {
userNameView.setText(userProfile.getString("name"));
} else {
userNameView.setText("");
}
if (userProfile.getString("location") != null) {
userLocationView.setText(userProfile.getString("location"));
} else {
userLocationView.setText("");
}
} catch (JSONException e) {
Log.d(TradelyApplication.TAG,
"Error parsing saved user data.");
}
// This is where the listView data task is called
new RemoteDataTask().execute();
}
}
private void onLogoutButtonClicked() {
// Log the user out
ParseUser.logOut();
// Go to the login view
startLoginActivity();
}
private void startLoginActivity() {
Intent intent = new Intent(getActivity(), MainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
}
答案 0 :(得分：1)
试试这个
在Listview
OnCreate
listview = (ListView) v.findViewById(R.id.userpostlistview);
并尝试..