java lang NullPointerException Attempt to invoke virtual method int android view View getImportantForAccessibility on a null object reference

Question

I m trying to put together a shopping list app  based on input fields  ArrayList  and ListView  The app will be based on Fragments  However  I have encountered a problem and I do not know how to solve it  I looked around on both Google and StackOverflow and I have found some information  However  I have not got it to work  Now I hope that I can get help with my code  I m relatively inexperienced in Android development  Main java import java util ArrayList   import android app Fragment  import android app FragmentManager  import android app FragmentTransaction  import android os Bundle  import android support v4 app FragmentActivity  import android view Menu  import android view MenuItem   public class Main extends FragmentActivity            ArrayList lt Detail gt  items   new ArrayList lt Detail gt         FragmentManager FM      FragmentTransaction FT      Input input   new Input              Override     protected void onCreate Bundle savedInstanceState            super onCreate savedInstanceState           setContentView R layout activity main                    replaceFragment R id container  input                   public void replaceFragment int container  Fragment fragment           FM   getFragmentManager            FT   FM beginTransaction                     FT replace container  fragment           FT commit                    Override     public boolean onCreateOptionsMenu Menu menu               Inflate the menu  this adds items to the action bar if it is present          getMenuInflater   inflate R menu main  menu           return true              Override     public boolean onOptionsItemSelected MenuItem item               Handle action bar item clicks here  The action bar will            automatically handle clicks on the Home Up button  so long            as you specify a parent activity in AndroidManifest xml          int id   item getItemId            if  id    R id action settings                return true                    return super onOptionsItemSelected item            ListAdapter java public class ListAdapter extends BaseAdapter        Context context      ArrayList lt Detail gt  items           public ListAdapter Context context  ArrayList lt Detail gt  items            this context   context          this items   items                  Override     public int getCount             return items size                Override     public Object getItem int position            return items get position               Override     public long getItemId int position            return items indexOf getItem position                Override     public View getView int position  View convertView  ViewGroup parent                     if convertView    null               LayoutInflater lInflater    LayoutInflater context getSystemService                      Activity LAYOUT INFLATER SERVICE                            convertView   lInflater inflate R layout list row  null                                     TextView title    TextView convertView findViewById R id itemTitle           CheckBox done    CheckBox convertView findViewById R id itemDone                             Detail detail position   items get position                    title setText detail position getTitle             done setChecked detail position isDone                      return null           List java import java util ArrayList   import android app ListFragment  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   public class List extends ListFragment implements OnItemClickListener       ArrayList lt Detail gt  items      ListAdapter adapter      private onClickListener OCL       interface onClickListener          public void onItemClick int id              public List ArrayList lt Detail gt  items            this items   items              Override     public View onCreateView LayoutInflater inflater  ViewGroup container              Bundle savedInstanceState             View root   inflater inflate R layout list layout  container  false           return root              Override     public void onActivityCreated Bundle savedInstanceState            super onActivityCreated savedInstanceState            if items    null               adapter   new ListAdapter getActivity    items               setListAdapter adapter               getListView   setOnItemClickListener this                          Override     public void onItemClick AdapterView lt   gt  parent  View view  int position              long id             if OCL    null               OCL onItemClick position                             list layout xml  lt  xml version  quot 1 0 quot  encoding  quot utf-8 quot   gt   lt LinearLayout xmlns android  quot http   schemas android com apk res android quot      android id  quot   id LinearLayout1 quot      android layout width  quot match parent quot      android layout height  quot match parent quot      android orientation  quot vertical quot   gt       lt ListView         android id  quot   id android list quot          android layout width  quot match parent quot          android layout height  quot match parent quot   gt       lt  ListView gt   lt  LinearLayout gt   list row  lt  xml version  quot 1 0 quot  encoding  quot utf-8 quot   gt   lt LinearLayout xmlns android  quot http   schemas android com apk res android quot      android layout width  quot match parent quot      android layout height  quot match parent quot      android orientation  quot horizontal quot      android padding  quot 10dp quot   gt       lt TextView         android id  quot   id itemTitle quot          android layout width  quot wrap content quot          android layout height  quot wrap content quot          android layout weight  quot 0 96 quot          android text  quot Medium Text quot          android textAppearance  quot  android attr textAppearanceMedium quot    gt       lt CheckBox         android id  quot   id itemDone quot          android layout width  quot wrap content quot          android layout height  quot wrap content quot          android text  quot Done quot    gt   lt  LinearLayout gt   activity main xml  lt RelativeLayout xmlns android  quot http   schemas android com apk res android quot      xmlns tools  quot http   schemas android com tools quot      android id  quot   id container quot      android layout width  quot match parent quot      android layout height  quot match parent quot      android paddingBottom  quot  dimen activity vertical margin quot      android paddingLeft  quot  dimen activity horizontal margin quot      android paddingRight  quot  dimen activity horizontal margin quot      android paddingTop  quot  dimen activity vertical margin quot      tools context  quot com example com hermods lab2 2 Main quot   gt   lt  RelativeLayout gt   Log 02-19 09 10 47 421  E AndroidRuntime 12745   Process  com example com hermods lab2 2  PID  12745 02-19 09 10 47 421  E AndroidRuntime 12745   java lang NullPointerException  Attempt to invoke virtual method  int android view View getImportantForAccessibility    on a null object reference 02-19 09 10 47 421  E AndroidRuntime 12745      at android widget AbsListView obtainView AbsListView java 2360  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget ListView makeAndAddView ListView java 1864  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget ListView fillDown ListView java 698  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget ListView fillFromTop ListView java 759  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget ListView layoutChildren ListView java 1673  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget AbsListView onLayout AbsListView java 2148  02-19 09 10 47 421  E AndroidRuntime 12745      at android view View layout View java 15596  02-19 09 10 47 421  E AndroidRuntime 12745      at android view ViewGroup layout ViewGroup java 4966  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget LinearLayout setChildFrame LinearLayout java 1703  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget LinearLayout layoutVertical LinearLayout java 1557  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget LinearLayout onLayout LinearLayout java 1466  02-19 09 10 47 421  E AndroidRuntime 12745      at android view View layout View java 15596  02-19 09 10 47 421  E AndroidRuntime 12745      at android view ViewGroup layout ViewGroup java 4966  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget RelativeLayout onLayout RelativeLayout java 1076  02-19 09 10 47 421  E AndroidRuntime 12745      at android view View layout View java 15596  02-19 09 10 47 421  E AndroidRuntime 12745      at android view ViewGroup layout ViewGroup java 4966  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget FrameLayout layoutChildren FrameLayout java 573  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget FrameLayout onLayout FrameLayout java 508  02-19 09 10 47 421  E AndroidRuntime 12745      at android view View layout View java 15596  02-19 09 10 47 421  E AndroidRuntime 12745      at android view ViewGroup layout ViewGroup java 4966  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget LinearLayout setChildFrame LinearLayout java 1703  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget LinearLayout layoutVertical LinearLayout java 1557  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget LinearLayout onLayout LinearLayout java 1466  02-19 09 10 47 421  E AndroidRuntime 12745      at android view View layout View java 15596  02-19 09 10 47 421  E AndroidRuntime 12745      at android view ViewGroup layout ViewGroup java 4966  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget FrameLayout layoutChildren FrameLayout java 573  02-19 09 10 47 421  E AndroidRuntime 12745      at android widget FrameLayout onLayout FrameLayout java 508  02-19 09 10 47 421  E AndroidRuntime 12745      at android view View layout View java 15596  02-19 09 10 47 421  E AndroidRuntime 12745      at android view ViewGroup layout ViewGroup java 4966  02-19 09 10 47 421  E AndroidRuntime 12745      at android view ViewRootImpl performLayout ViewRootImpl java 2072  02-19 09 10 47 421  E AndroidRuntime 12745      at android view ViewRootImpl performTraversals ViewRootImpl java 1829  02-19 09 10 47 421  E AndroidRuntime 12745      at android view ViewRootImpl doTraversal ViewRootImpl java 1054  02-19 09 10 47 421  E AndroidRuntime 12745      at android view ViewRootImpl TraversalRunnable run ViewRootImpl java 5779  02-19 09 10 47 421  E AndroidRuntime 12745      at android view Choreographer CallbackRecord run Choreographer java 767  02-19 09 10 47 421  E AndroidRuntime 12745      at android view Choreographer doCallbacks Choreographer java 580  02-19 09 10 47 421  E AndroidRuntime 12745      at android view Choreographer doFrame Choreographer java 550  02-19 09 10 47 421  E AndroidRuntime 12745      at android view Choreographer FrameDisplayEventReceiver run Choreographer java 753  02-19 09 10 47 421  E AndroidRuntime 12745      at android os Handler handleCallback Handler java 739  02-19 09 10 47 421  E AndroidRuntime 12745      at android os Handler dispatchMessage Handler java 95  02-19 09 10 47 421  E AndroidRuntime 12745      at android os Looper loop Looper java 135  02-19 09 10 47 421  E AndroidRuntime 12745      at android app ActivityThread main ActivityThread java 5221  02-19 09 10 47 421  E AndroidRuntime 12745      at java lang reflect Method invoke Native Method  02-19 09 10 47 421  E AndroidRuntime 12745      at java lang reflect Method invoke Method java 372  02-19 09 10 47 421  E AndroidRuntime 12745      at com android internal os ZygoteInit MethodAndArgsCaller run ZygoteInit java 899  02-19 09 10 47 421  E AndroidRuntime 12745      at com android internal os ZygoteInit main ZygoteInit java 694

User · Accepted Answer

In your public View getView method change return null  to  return convertView

User · Answer

in your baseadapter class constructor try to initialize LayoutInflater  normally i preferred this way   public ClassBaseAdapter Context context ArrayList lt Integer gt  listLoanAmount        this context   context      this listLoanAmount   listLoanAmount      this layoutInflater   LayoutInflater from context       at the top of the class create LayoutInflater variable  hope this will help you

User · Answer

it sometimes occurs when we use a custom adapter in any activity of fragment   and we return null object i e null view so the activity gets confused which view to load   so that is why this exception occurs  shows the position where to change the view

User · Answer

use    return convertView    Code   public View getView final int position  View convertView  ViewGroup parent           convertView   null       if  convertView    null             LayoutInflater mInflater    LayoutInflater  context getSystemService Activity LAYOUT INFLATER SERVICE           convertView   mInflater inflate R layout list item  null                 TextView tv    TextView  convertView findViewById R id name           Button rm btn    Button  convertView findViewById R id rm btn            Model m   modelList get position           tv setText m getName                 click listener for remove button                     rm btn setOnClickListener new View OnClickListener                  Override             public void onClick View v                    modelList remove position                   notifyDataSetChanged                                             use    return convertView      return convertView

User · Answer

My silly mistake was this  change    to    if convertView    null        lt ---- HERE                  LayoutInflater layoutInflater   LayoutInflater from z selBoardElectricity this                   convertView   layoutInflater inflate R layout listview board alert  null                    TextView textView   convertView findViewById R id board name tv                   ImageView imageView   convertView findViewById R id board imageview                    textView setText text list get position                    imageView setImageDrawable imageAddressList get position                     convertView setOnClickListener new View OnClickListener                          Override                     public void onClick View v                            Intent intent   new Intent                            intent putExtra  quot MESSAGE quot   text list get pos                            setResult 98  intent                           finish                                                            return convertView

[android] java.lang.NullPointerException: Attempt to invoke virtual method 'int android.view.View.getImportantForAccessibility()' on a null object reference

Examples related to android

Examples related to android-layout

Examples related to android-fragments

Examples related to android-listview