RecyclerView move items to end based on checkbox

Question

Perhaps this is a simple question, but I didn't find a solution yet.

I have a RecyclerView with CardView's as elements and each CardView has a CheckBox view inside it.

My intention is to make a list of Todo's, and when the user checks the checkbox, the checked item will move to the end of the list.

Currently my adapter is:

    private class Adapter extends RecyclerView.Adapter<Adapter.ViewHolder>{

    protected class ViewHolder extends RecyclerView.ViewHolder
    {
        TextView todoTextView;
        TextView addedOnTextView;
        TextView dueToDateTextView;
        TextView dueToHourTextView;
        CheckBox checkBox;
        protected ViewHolder(CardView cv)
        {
            super(cv);
            this.todoTextView = (TextView) cv.findViewById(R.id.todo_text);
            this.addedOnTextView = (TextView) cv.findViewById(R.id.added_on);
            this.dueToDateTextView = (TextView) cv.findViewById(R.id.due_to_date);
            this.dueToHourTextView = (TextView) cv.findViewById(R.id.due_to_hour);
            this.checkBox = (CheckBox)cv.findViewById(R.id.checkbox);
        }
    }
    private final String[] COLORS = {"#64B5F6", "#F44336"};
    private ArrayList<Todo> mTodos;

    public Adapter()
    {
        this.mTodos = new ArrayList<>();
    }

    public void addItem(Todo message)
    {
        this.mTodos.add(message);
        notifyItemInserted(getItemCount());
    }

    @Override
    public int getItemCount() {
        return mTodos.size();
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        CardView cView = (CardView) LayoutInflater.from(parent.getContext()).inflate(R.layout.todolist_item,
                parent, false);
        cView.setCardBackgroundColor(Color.parseColor(COLORS[viewType]));
        ViewHolder hView = new ViewHolder(cView);
        return hView;
    }

    @Override
    public int getItemViewType(int position) {
        return position % 2;
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, final int position) {
        final Todo currentTodo = mTodos.get(position);

        holder.todoTextView.setText(currentTodo.getmTodo());
        holder.dueToDateTextView.setText(currentTodo.getDueToDate());
        holder.dueToHourTextView.setText(currentTodo.getDueToHour());
        holder.addedOnTextView.setText(currentTodo.getAddedStr());
        holder.checkBox.setChecked(currentTodo.isChecked());
        final int myPos = holder.getAdapterPosition();
        holder.checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                currentTodo.setChecked();
                buttonView.setEnabled(false);
                mTodos.add(mTodos.remove(myPos));
                notifyDataSetChanged();
            }
        });
    }

I know this is not the correct way of doing this, and currently I'm getting the next exception:

java.lang.IllegalStateException: Cannot call this method while RecyclerView is computing a layout or scrolling

I know the OnCheckedStateChanged method should be defined in the OnCreateViewHolder method, but there I don't have the position of the current item to move to the end of the list.

Can anyone help me with that task?

The onCheckedStateChanged in OnBindViewHolder, specifically the call for notifyDataSetChange() — dor132, Mar 15 '17 at 23:32
check [this](http://stackoverflow.com/questions/27070220/recycleview-notifydatasetchanged-illegalstateexception) out. — xiaoyuan, Mar 16 '17 at 02:17

score 0 · Accepted Answer · answered Mar 15 '17 at 23:55

You should move your logic in viewHolder :

private class Adapter extends RecyclerView.Adapter<Adapter.ViewHolder>{
    protected class ViewHolder extends RecyclerView.ViewHolder
    {
        TextView todoTextView;
        TextView addedOnTextView;
        TextView dueToDateTextView;
        TextView dueToHourTextView;
        CheckBox checkBox;
        protected ViewHolder(CardView cv)
        {
            super(cv);
            this.todoTextView = (TextView) cv.findViewById(R.id.todo_text);
            this.addedOnTextView = (TextView) cv.findViewById(R.id.added_on);
            this.dueToDateTextView = (TextView) cv.findViewById(R.id.due_to_date);
            this.dueToHourTextView = (TextView) cv.findViewById(R.id.due_to_hour);
            this.checkBox = (CheckBox)cv.findViewById(R.id.checkbox);
            this.checkBox.setOnCheckChangeListener(this);
        }

        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
            Todo currentTodo = mTodos.get(getAdapterPosition());
            if(!onBind) {
                currentTodo.setChecked();
                buttonView.setEnabled(false);
                mTodos.add(mTodos.remove(getAdapterPosition()));
                notifyDataSetChanged();
            }
         }
    }
    private final String[] COLORS = {"#64B5F6", "#F44336"};
    private ArrayList<Todo> mTodos;
    public Adapter()
    {
        this.mTodos = new ArrayList<>();
    }
    public void addItem(Todo message)
    {
        this.mTodos.add(message);
        notifyItemInserted(getItemCount());
    }
    @Override
    public int getItemCount() {
        return mTodos.size();
    }
    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        CardView cView = (CardView) LayoutInflater.from(parent.getContext()).inflate(R.layout.todolist_item,
                parent, false);
        cView.setCardBackgroundColor(Color.parseColor(COLORS[viewType]));
        ViewHolder hView = new ViewHolder(cView);
        return hView;
    }
    @Override
    public int getItemViewType(int position) {
        return position % 2;
    }
    @Override
    public void onBindViewHolder(ViewHolder holder, final int position) {
        final Todo currentTodo = mTodos.get(position);
        holder.todoTextView.setText(currentTodo.getmTodo());
        holder.dueToDateTextView.setText(currentTodo.getDueToDate());
        holder.dueToHourTextView.setText(currentTodo.getDueToHour());
        holder.addedOnTextView.setText(currentTodo.getAddedStr());
        holder.checkBox.setChecked(currentTodo.isChecked());

    }

I can't try for now , let me know if is helping you.

Sorry for my english.

RecyclerView move items to end based on checkbox

1 Answers1