Android: ListView with RelativeLayout -> NullReference

Question

I'm trying to implement a ListView relative layout using a ViewHolder. In getView(), I'm running into a NullReference. I've modeled the code after an example I found here on Stack Overflow. Here's the code:

private ViewHolder mViewHolder;

public View getView(int position, View convertView, ViewGroup parent) {

    final ToDoItem toDoItem = mItems.get(position);

    if (convertView==null){
        mViewHolder = new ViewHolder();
        LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = inflater.inflate(R.layout.todo_item, parent, false);

        RelativeLayout itemLayout = (RelativeLayout) convertView.findViewById(R.id.RelativeLayout1);

        mViewHolder.tvTitle = (TextView) convertView.findViewById((R.id.title));
        mViewHolder.cbStatus = (CheckBox) convertView.findViewById(R.id.statusCheckBox);
        mViewHolder.tvPriority = (TextView) convertView.findViewById(R.id.priority);
        mViewHolder.tvDate = (TextView) convertView.findViewById(R.id.date);

        convertView.setTag(mViewHolder);
    }else{
        mViewHolder = (ViewHolder) convertView.getTag();
    }

    --->mViewHolder.tvTitle.setText(toDoItem.getTitle());
    mViewHolder.tvPriority.setText(toDoItem.getPriority().toString());
    mViewHolder.tvDate.setText(toDoItem.getDate().toString());
    mViewHolder.cbStatus.setChecked(false);

    if (toDoItem.getStatus().toString() == "DONE") mViewHolder.cbStatus.setChecked(true);


    final TextView titleView = mViewHolder.tvTitle;
    final CheckBox statusView = mViewHolder.cbStatus;
    final TextView priorityView = mViewHolder.tvPriority;
    final TextView dateView = mViewHolder.tvDate;

    itemLayout.addView(titleView);
    itemLayout.addView(statusView);
    itemLayout.addView(priorityView);
    itemLayout.addView(dateView);

    return convertView;

The NullReference is thrown on the line following the closing bracket of the

if (convertView == null)

and is marked with ---->

I've tried to assign different entities to the ViewHolder with little success. I'd appreciate any help anyone has to offer. Thanks in advance!

Markb

The null reference is referencing to mViewHolder or toDoItem? This question may resolt your doubts. Try testing every object if is null. In my opinion, is a "ToDoItem" object null reference, but confirm that. — Neonamu, Jun 03 '15 at 15:05
Sorry, I didn't include that bit of info: toDoItem is correctly populated. The null is on mViewHolder. — mjb, Jun 04 '15 at 13:08
Let me further refine my last response: mViewHolder exists, but the tvTitle field contains a null (as do all of the other TextView fields in the object). Makes sense to me since all that's happened up to that point has been to construct the elements of the view holder. The view holder structure is there, as is the completely populated toDoItem. why can I not assign a legitimate value to the mViewHolder field? — mjb, Jun 04 '15 at 16:40
This null expcetion, comes when convertView is null or with convertVIew != null? I recommend you to put convertView.setTag(mViewHolder); at the end of method. Why? — Neonamu, Jun 06 '15 at 14:08

score 0 · Answer 1 · answered Jun 03 '15 at 15:03

0

toDoItem Could be null as well if that object in the list is null.

answered Jun 03 '15 at 15:03

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Sorry, I didn't include that bit of info: toDoItem is correctly populated. The null is on mViewHolder. – mjb Jun 04 '15 at 13:27
You mViewHolder should be inside the `getView` method. Try changing this and see if it changes the outcome. – Catalina Jun 04 '15 at 15:57
No change. Scoping the view holder at the module level only makes it visible everywhere in the class, there's no functional consideration. – mjb Jun 04 '15 at 17:34

Android: ListView with RelativeLayout -> NullReference

1 Answers1