Cannot resolve getSystemService method in ListView adapter

Question

I am working through John Horton\'s Android Programming for Beginners, and am currently attempting to create a note-taking app. Horton has just introduced ListVie

Answer 1

In my views, if you are learning then learn RecyclerView. bcz it is better than ListView. i am not saying that ListView has been depricated. But there alot of internal things in which RecyclerView is better.

Following is example of Adapter

public class NoteAdapter extends BaseAdapter {

    List mNoteList = new ArrayList();

    Context context;

    public NoteAdapter(Context context){
        this.context = context;
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 

    }

    @Override
    public int getCount(){
        return mNoteList.size();
    }

    @Override
    public Note getItem(int whichItem){
        return mNoteList.get(whichItem);
    }

    @Override
    public long getItemId(int whichItem){
        return whichItem;
    }

    @Override
    public View getView(int whichItem, View view, ViewGroup viewGroup){

        // check if view has been inflated already 
        if (view == null){

            view = inflater.inflate(R.layout.listitem, viewGroup, false);

        }

        return view;
    }

} 

Inside MainActivity.java

NoteAdapter noteA = new NoteAdapter(MainActivity.this);

OR

NoteAdapter noteA = new NoteAdapter(getContext());

OR

NoteAdapter noteA = new NoteAdapter(getActivity);

// if in Fragment

OR

NoteAdapter noteA = new NoteAdapter(getApplicationContext);

// will work but no need to use it. bcz this is context of whole application. For an adapter you don't need context of whole application.