nullpointerexception

问题 I have a class in another java file that I'm calling in my MainActivity. I need to inflate some layouts in the external class. The problem I'm having is specifying the context, because when I try to inflate the layouts I get a Null Pointer Exception. The class doesn't have it's own onCreate() method so I need to pass the context from my MainActivity? Not sure how to go about it. This is causing me the NullPointerException : Context context = getApplicationContext(); LayoutInflater inflater =

问题 My work computer that Eclipse is installed on does not have internet connectivity due to work related issues so all code and LogCat text has been hand typed instead of copy and pasted since I am on a separate laptop that Eclipse is installed right now. So bear with me for any typos. Now to the issue. In the new version of my app, I am making it Spanish supported. I localized all my strings in strings.xml . Below is my Java code that I am not usuing to implement. public class SplashScreen

问题 I am creating a method which will take int n as a parameter, convert a previously initialized String into an integer array, add 1 to each index n times, create a new char array from each increment of the int array via casting, then convert all n char arrays into new strings and print them to the screen. Netbeans throws a NullPointerException in my current project, and I'm not sure why. Could someone explain why this error is present and what I ought to do to fix it? Relevant Class: https:/

问题 I am trying to execute Javascript function called " returnAllLinkTexts() " on the DOM html page loaded via my Java application. Below line is executed by a Swing Buton. myscript = browser.executeJavascript("returnAllLinkTexts()").toString(); //Line 407 Once in a while I get the following exception. The Java application does not terminate or crash. Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException com.demo.Main$BigButtonListener.actionPerformed(Main.java:407) I have tried

问题 I am trying to get an id from URL but getting the null pointer exception java.lang.NullPointerException: Attempt to read from field 'java.lang.String com.hex.encode.ID_Model$User.id' on a null object reference at com.hex.encode.Home$3.onResponse(Home.java:99) and this is the code I am using to get the id: private void GetID() { Call<ID_Model> idcall = fetchdata.getIdService().getID(user_search); idcall.enqueue(new Callback<ID_Model>() { @Override public void onResponse(@NonNull Call<ID_Model>

问题 I am displaying a ordered food list. A FloatingActionButton is placed on each food item(productId) at the ordered list, and I want to show a rating alert dialog to let user rate the food after clicking the FloatingActionButton. How do I get each of the productId when user click on the Fab button? Because I need to display the ratings at another food detail page based on the productId. I am just a beginner learning so don't really understand.Thanks OrderDetailAdapter.java class MyViewHolder

问题 I have followed the tutorial found here, and I am getting a NullPointerException. I've searched on StackOverflow and Google for a possible solution to this, but to no avail. Below you will see my code and my LogCat. Any ideas on what I should do to fix this? XMLParsingExample.java (Line 57 = where the NullPointerException is occurring): package com.androidpeople.xml.parsing; import java.net.URL; import javax.xml.parsers.SAXParser; import javax.xml.parsers.SAXParserFactory; import org.xml.sax

问题 I am working on websocket communication with Autobahn. On the main.class of my app, I set to call 'connect()' when users click a button. // Toggle Button event tButton = (ToggleButton) findViewById(R.id.toggleButton1); tButton.setOnCheckedChangeListener(new OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { if(isChecked){ }else{ } } }); And after that, there is MyOffers.class, and if this class is accessed, MyOffers_Fragment

问题 I am not sure what started this problem. I submitted it as a bug to Eclipse but they closed it, stating it is a JBoss extension problem. However, this problem doesn't occur in my other workspace (both utilize the JBoss tools). It occurs every time I hit Ctrl + Shift + T to open a new type. It only reports the "Cache Refresh" error. Then when I type in a search string and hit OK, it pops up both the "Cache Refresh" error and a "Items filtering" error. Both of these report NPEs. I inspected the

问题 I am using Retroft and GSON for parsing the response. My onResponse code is like below @Override public void onResponse(@NonNull Call<ResultList> call, @NonNull Response<ResultList> response) { if (response.isSuccessful()) { if (response.body() != null && response.body().getSuccess() == 1) { ................ I am checking response.body() != null and also response.isSuccessful() . Still I am getting warning in Android studio on line response.body().getSuccess() . How to avoid this warning? I